156672561 has 16 divisors (see below), whose sum is σ = 221876928. Its totient is φ = 97996800.

The previous prime is 156672547. The next prime is 156672569. The reversal of 156672561 is 165276651.

It is not a de Polignac number, because 156672561 - 2⁶ = 156672497 is a prime.

It is not an unprimeable number, because it can be changed into a prime (156672569) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 12241 + ... + 21521.

It is an arithmetic number, because the mean of its divisors is an integer number (13867308).

Almost surely, 2^156672561 is an apocalyptic number.

It is an amenable number.

156672561 is a deficient number, since it is larger than the sum of its proper divisors (65204367).

156672561 is a wasteful number, since it uses less digits than its factorization.

156672561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9632.

The product of its digits is 75600, while the sum is 39.

The square root of 156672561 is about 12516.8910277273. The cubic root of 156672561 is about 539.0937715125.

The spelling of 156672561 in words is "one hundred fifty-six million, six hundred seventy-two thousand, five hundred sixty-one".