31671972 has 60 divisors (see below), whose sum is σ = 84090160. Its totient is φ = 10392624.

The previous prime is 31671953. The next prime is 31671977. The reversal of 31671972 is 27917613.

It is a happy number.

It is a super-2 number, since 2×31671972² = 2006227620737568, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is not an unprimeable number, because it can be changed into a prime (31671977) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 20979 + ... + 22437.

Almost surely, 2^31671972 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 31671972, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (42045080).

31671972 is an abundant number, since it is smaller than the sum of its proper divisors (52418188).

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

31671972 is a wasteful number, since it uses less digits than its factorization.

31671972 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1542 (or 1531 counting only the distinct ones).

The product of its digits is 15876, while the sum is 36.

The square root of 31671972 is about 5627.7857102061. The cubic root of 31671972 is about 316.3916657146.

The spelling of 31671972 in words is "thirty-one million, six hundred seventy-one thousand, nine hundred seventy-two".