161689293504 has 448 divisors, whose sum is σ = 542187993600. Its totient is φ = 46931705856.

The previous prime is 161689293499. The next prime is 161689293671. The reversal of 161689293504 is 405392986161.

It is a super-2 number, since 2×161689293504² (a number of 23 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 23996824 + ... + 24003560.

Almost surely, 2^161689293504 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 161689293504, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (271093996800).

161689293504 is an abundant number, since it is smaller than the sum of its proper divisors (380498700096).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

161689293504 is a wasteful number, since it uses less digits than its factorization.

161689293504 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6837 (or 6821 counting only the distinct ones).

The product of its (nonzero) digits is 2799360, while the sum is 54.

The spelling of 161689293504 in words is "one hundred sixty-one billion, six hundred eighty-nine million, two hundred ninety-three thousand, five hundred four".