31142556 has 60 divisors (see below), whose sum is σ = 81942168. Its totient is φ = 10313568.

The previous prime is 31142543. The next prime is 31142557. The reversal of 31142556 is 65524113.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31142557) 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, 89575 + ... + 89921.

Almost surely, 2^31142556 is an apocalyptic number.

31142556 is a gapful number since it is divisible by the number (36) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 31142556, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (40971084).

31142556 is an abundant number, since it is smaller than the sum of its proper divisors (50799612).

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

31142556 is a wasteful number, since it uses less digits than its factorization.

31142556 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 640 (or 629 counting only the distinct ones).

The product of its digits is 3600, while the sum is 27.

The square root of 31142556 is about 5580.5515856410. The cubic root of 31142556 is about 314.6188587436.

Adding to 31142556 its reverse (65524113), we get a palindrome (96666669).

The spelling of 31142556 in words is "thirty-one million, one hundred forty-two thousand, five hundred fifty-six".