31400020 has 24 divisors (see below), whose sum is σ = 69819624. Its totient is φ = 11821056.

The previous prime is 31399999. The next prime is 31400021. The reversal of 31400020 is 2000413.

It can be written as a sum of positive squares in 4 ways, for example, as 8225424 + 23174596 = 2868^2 + 4814^2 .

It is a super-2 number, since 2×31400020² = 1971922512000800, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (10).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31400021) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 45837 + ... + 46516.

It is an arithmetic number, because the mean of its divisors is an integer number (2909151).

Almost surely, 2^31400020 is an apocalyptic number.

It is an amenable number.

31400020 is an abundant number, since it is smaller than the sum of its proper divisors (38419604).

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

31400020 is a wasteful number, since it uses less digits than its factorization.

31400020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 92379 (or 92377 counting only the distinct ones).

The product of its (nonzero) digits is 24, while the sum is 10.

The square root of 31400020 is about 5603.5720750250. The cubic root of 31400020 is about 315.4834936692.

Adding to 31400020 its reverse (2000413), we get a palindrome (33400433).

The spelling of 31400020 in words is "thirty-one million, four hundred thousand, twenty".