31191642 has 40 divisors (see below), whose sum is σ = 72158592. Its totient is φ = 10060200.

The previous prime is 31191631. The next prime is 31191683. The reversal of 31191642 is 24619113.

31191642 is a `hidden beast` number, since 3 + 1 + 19 + 1 + 642 = 666.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is an unprimeable number.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 1917 + ... + 8127.

Almost surely, 2^31191642 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 31191642, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (36079296).

31191642 is an abundant number, since it is smaller than the sum of its proper divisors (40966950).

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

31191642 is a wasteful number, since it uses less digits than its factorization.

31191642 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6256 (or 6247 counting only the distinct ones).

The product of its digits is 1296, while the sum is 27.

The square root of 31191642 is about 5584.9478063810. The cubic root of 31191642 is about 314.7840697022.

It can be divided in two parts, 3119 and 1642, that added together give a square (4761 = 69²).

The spelling of 31191642 in words is "thirty-one million, one hundred ninety-one thousand, six hundred forty-two".