161552160421 has 4 divisors (see below), whose sum is σ = 161677493100. Its totient is φ = 161426827744.

The previous prime is 161552160401. The next prime is 161552160461. The reversal of 161552160421 is 124061255161.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 124061255161 = 307 ⋅404108323.

It can be written as a sum of positive squares in 2 ways, for example, as 153163432321 + 8388728100 = 391361^2 + 91590^2 .

It is a cyclic number.

It is not a de Polignac number, because 161552160421 - 2⁷ = 161552160293 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161552160401) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 62664406 + ... + 62666983.

It is an arithmetic number, because the mean of its divisors is an integer number (40419373275).

Almost surely, 2^161552160421 is an apocalyptic number.

It is an amenable number.

161552160421 is a deficient number, since it is larger than the sum of its proper divisors (125332679).

161552160421 is a wasteful number, since it uses less digits than its factorization.

161552160421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 125332678.

The product of its (nonzero) digits is 14400, while the sum is 34.

The spelling of 161552160421 in words is "one hundred sixty-one billion, five hundred fifty-two million, one hundred sixty thousand, four hundred twenty-one".