161972590 has 16 divisors (see below), whose sum is σ = 313977888. Its totient is φ = 59805216.

The previous prime is 161972581. The next prime is 161972597. The reversal of 161972590 is 95279161.

161972590 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a super-2 number, since 2×161972590² = 52470239822616200, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161972597) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 622842 + ... + 623101.

It is an arithmetic number, because the mean of its divisors is an integer number (19623618).

Almost surely, 2^161972590 is an apocalyptic number.

161972590 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

161972590 is a deficient number, since it is larger than the sum of its proper divisors (152005298).

161972590 is a wasteful number, since it uses less digits than its factorization.

161972590 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1245963.

The product of its (nonzero) digits is 34020, while the sum is 40.

The square root of 161972590 is about 12726.8452493145. The cubic root of 161972590 is about 545.1054308837.

The spelling of 161972590 in words is "one hundred sixty-one million, nine hundred seventy-two thousand, five hundred ninety".