31440432 has 40 divisors (see below), whose sum is σ = 81423360. Its totient is φ = 10454080.

The previous prime is 31440427. The next prime is 31440449. The reversal of 31440432 is 23404413.

It is a junction number, because it is equal to n+sod(n) for n = 31440399 and 31440408.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 34057 + ... + 34967.

It is an arithmetic number, because the mean of its divisors is an integer number (2035584).

Almost surely, 2^31440432 is an apocalyptic number.

It is an amenable number.

31440432 is an abundant number, since it is smaller than the sum of its proper divisors (49982928).

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

31440432 is a wasteful number, since it uses less digits than its factorization.

31440432 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1641 (or 1635 counting only the distinct ones).

The product of its (nonzero) digits is 1152, while the sum is 21.

The square root of 31440432 is about 5607.1768297424. The cubic root of 31440432 is about 315.6187786507.

Adding to 31440432 its reverse (23404413), we get a palindrome (54844845).

The spelling of 31440432 in words is "thirty-one million, four hundred forty thousand, four hundred thirty-two".