4157121609 has 20 divisors (see below), whose sum is σ = 6424163460. Its totient is φ = 2675846880.

The previous prime is 4157121541. The next prime is 4157121611. The reversal of 4157121609 is 9061217514.

4157121609 is a `hidden beast` number, since 4 + 1 + 571 + 21 + 60 + 9 = 666.

4157121609 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 2 ways, for example, as 3519811584 + 637310025 = 59328^2 + 25245^2 .

It is a de Polignac number, because none of the positive numbers 2^k-4157121609 is a prime.

It is not an unprimeable number, because it can be changed into a prime (4157121629) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 882522 + ... + 887219.

It is an arithmetic number, because the mean of its divisors is an integer number (321208173).

Almost surely, 2^4157121609 is an apocalyptic number.

It is an amenable number.

4157121609 is a deficient number, since it is larger than the sum of its proper divisors (2267041851).

4157121609 is a wasteful number, since it uses less digits than its factorization.

4157121609 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1769782 (or 1769773 counting only the distinct ones).

The product of its (nonzero) digits is 15120, while the sum is 36.

The square root of 4157121609 is about 64475.7443462268. The cubic root of 4157121609 is about 1607.9192812845.

The spelling of 4157121609 in words is "four billion, one hundred fifty-seven million, one hundred twenty-one thousand, six hundred nine".