31699881 has 6 divisors (see below), whose sum is σ = 45788730. Its totient is φ = 21133248.

The previous prime is 31699879. The next prime is 31699897. The reversal of 31699881 is 18899613.

It can be written as a sum of positive squares in only one way, i.e., 30074256 + 1625625 = 5484^2 + 1275^2 .

It is not a de Polignac number, because 31699881 - 2¹ = 31699879 is a prime.

It is a super-2 number, since 2×31699881² = 2009764910828322, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (31699831) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1761096 + ... + 1761113.

It is an arithmetic number, because the mean of its divisors is an integer number (7631455).

Almost surely, 2^31699881 is an apocalyptic number.

It is an amenable number.

31699881 is a deficient number, since it is larger than the sum of its proper divisors (14088849).

31699881 is a wasteful number, since it uses less digits than its factorization.

31699881 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3522215 (or 3522212 counting only the distinct ones).

The product of its digits is 93312, while the sum is 45.

The square root of 31699881 is about 5630.2647362269. The cubic root of 31699881 is about 316.4845720713.

The spelling of 31699881 in words is "thirty-one million, six hundred ninety-nine thousand, eight hundred eighty-one".