31396890 has 64 divisors (see below), whose sum is σ = 86575104. Its totient is φ = 7138368.

The previous prime is 31396889. The next prime is 31396913. The reversal of 31396890 is 9869313.

It is an unprimeable number.

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 31 ways as a sum of consecutive naturals, for example, 64227 + ... + 64713.

It is an arithmetic number, because the mean of its divisors is an integer number (1352736).

Almost surely, 2^31396890 is an apocalyptic number.

31396890 is a gapful number since it is divisible by the number (30) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 31396890, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (43287552).

31396890 is an abundant number, since it is smaller than the sum of its proper divisors (55178214).

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

31396890 is a wasteful number, since it uses less digits than its factorization.

31396890 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 811.

The product of its (nonzero) digits is 34992, while the sum is 39.

The square root of 31396890 is about 5603.2927819274. The cubic root of 31396890 is about 315.4730107019.

The spelling of 31396890 in words is "thirty-one million, three hundred ninety-six thousand, eight hundred ninety".