161292260607921 has 45 divisors (see below), whose sum is σ = 241545456444369. Its totient is φ = 107259871658400.

The previous prime is 161292260607913. The next prime is 161292260608019. The reversal of 161292260607921 is 129706062292161.

It is a happy number.

The square root of 161292260607921 is 12700089.

It is a perfect power (a square), and thus also a powerful number.

161292260607921 is a `hidden beast` number, since 1 + 6 + 1 + 2 + 9 + 2 + 2 + 6 + 0 + 607 + 9 + 21 = 666.

161292260607921 is digitally balanced in base 2 and base 4, because in such bases it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 4 ways, for example, as 22695324409521 + 138596936198400 = 4763961^2 + 11772720^2 .

It is not a de Polignac number, because 161292260607921 - 2³ = 161292260607913 is a prime.

It is a Smith number, since the sum of its digits (54) coincides with the sum of the digits of its prime factors.

It is not an unprimeable number, because it can be changed into a prime (161292260607911) by changing a digit.

It is a polite number, since it can be written in 44 ways as a sum of consecutive naturals, for example, 52692667731 + ... + 52692670791.

Almost surely, 2^{161292260607921} is an apocalyptic number.

161292260607921 is the 12700089-th square number.

161292260607921 is the 6350045-th centered octagonal number.

It is an amenable number.

161292260607921 is a deficient number, since it is larger than the sum of its proper divisors (80253195836448).

161292260607921 is an frugal number, since it uses more digits than its factorization.

161292260607921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7056 (or 3525 counting only the distinct ones).

The product of its (nonzero) digits is 1959552, while the sum is 54.

The spelling of 161292260607921 in words is "one hundred sixty-one trillion, two hundred ninety-two billion, two hundred sixty million, six hundred seven thousand, nine hundred twenty-one".