31261668 has 12 divisors (see below), whose sum is σ = 72943920. Its totient is φ = 10420552.

The previous prime is 31261667. The next prime is 31261673. The reversal of 31261668 is 86616213.

It is a tau number, because it is divible by the number of its divisors (12).

It is a super-2 number, since 2×31261668² = 1954583772284448, which contains 22 as substring.

It is a Smith number, since the sum of its digits (33) coincides with the sum of the digits of its prime factors.

It is not an unprimeable number, because it can be changed into a prime (31261663) 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 3 ways as a sum of consecutive naturals, for example, 1302558 + ... + 1302581.

It is an arithmetic number, because the mean of its divisors is an integer number (6078660).

Almost surely, 2^31261668 is an apocalyptic number.

It is an amenable number.

31261668 is an abundant number, since it is smaller than the sum of its proper divisors (41682252).

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

31261668 is a wasteful number, since it uses less digits than its factorization.

31261668 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2605146 (or 2605144 counting only the distinct ones).

The product of its digits is 10368, while the sum is 33.

The square root of 31261668 is about 5591.2134639987. The cubic root of 31261668 is about 315.0194596192.

The spelling of 31261668 in words is "thirty-one million, two hundred sixty-one thousand, six hundred sixty-eight".