180640731 has 4 divisors (see below), whose sum is σ = 240854312. Its totient is φ = 120427152.

The previous prime is 180640729. The next prime is 180640799. The reversal of 180640731 is 137046081.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 180640731 - 2¹ = 180640729 is a prime.

It is a super-2 number, since 2×180640731² = 65262147392428722, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (180640631) 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, 30106786 + ... + 30106791.

It is an arithmetic number, because the mean of its divisors is an integer number (60213578).

Almost surely, 2^180640731 is an apocalyptic number.

180640731 is a deficient number, since it is larger than the sum of its proper divisors (60213581).

180640731 is an equidigital number, since it uses as much as digits as its factorization.

180640731 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 60213580.

The product of its (nonzero) digits is 4032, while the sum is 30.

The square root of 180640731 is about 13440.2652875604. The cubic root of 180640731 is about 565.2907694870.

The spelling of 180640731 in words is "one hundred eighty million, six hundred forty thousand, seven hundred thirty-one".