31070900 has 108 divisors (see below), whose sum is σ = 83268108. Its totient is φ = 9999360.

The previous prime is 31070867. The next prime is 31070903. The reversal of 31070900 is 907013.

It can be written as a sum of positive squares in 6 ways, for example, as 23716 + 31047184 = 154^2 + 5572^2 .

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31070903) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 83114 + ... + 83486.

It is an arithmetic number, because the mean of its divisors is an integer number (771001).

Almost surely, 2^31070900 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 31070900, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (41634054).

31070900 is an abundant number, since it is smaller than the sum of its proper divisors (52197208).

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

31070900 is a wasteful number, since it uses less digits than its factorization.

31070900 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 418 (or 404 counting only the distinct ones).

The product of its (nonzero) digits is 189, while the sum is 20.

The square root of 31070900 is about 5574.1277344532. The cubic root of 31070900 is about 314.3773709452.

Adding to 31070900 its reverse (907013), we get a palindrome (31977913).

The spelling of 31070900 in words is "thirty-one million, seventy thousand, nine hundred".