31085029640 has 96 divisors (see below), whose sum is σ = 81907119000. Its totient is φ = 10586096640.

The previous prime is 31085029637. The next prime is 31085029663. The reversal of 31085029640 is 4692058013.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 8151561796 + 22933467844 = 90286^2 + 151438^2 .

It is a super-3 number, since 3×31085029640³ (a number of 32 digits) contains 333 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 31085029594 and 31085029603.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 238820 + ... + 345260.

Almost surely, 2^31085029640 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 31085029640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (40953559500).

31085029640 is an abundant number, since it is smaller than the sum of its proper divisors (50822089360).

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

31085029640 is a wasteful number, since it uses less digits than its factorization.

31085029640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 106615 (or 106604 counting only the distinct ones).

The product of its (nonzero) digits is 51840, while the sum is 38.

The spelling of 31085029640 in words is "thirty-one billion, eighty-five million, twenty-nine thousand, six hundred forty".