31425661 has 12 divisors (see below), whose sum is σ = 33138396. Its totient is φ = 29789760.

The previous prime is 31425643. The next prime is 31425683. The reversal of 31425661 is 16652413.

It can be written as a sum of positive squares in 2 ways, for example, as 9803161 + 21622500 = 3131^2 + 4650^2 .

It is not a de Polignac number, because 31425661 - 2⁵ = 31425629 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31425461) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 50625 + ... + 51241.

It is an arithmetic number, because the mean of its divisors is an integer number (2761533).

Almost surely, 2^31425661 is an apocalyptic number.

31425661 is a gapful number since it is divisible by the number (31) formed by its first and last digit.

It is an amenable number.

31425661 is a deficient number, since it is larger than the sum of its proper divisors (1712735).

31425661 is an equidigital number, since it uses as much as digits as its factorization.

31425661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 732 (or 701 counting only the distinct ones).

The product of its digits is 4320, while the sum is 28.

The square root of 31425661 is about 5605.8595237483. The cubic root of 31425661 is about 315.5693440537.

The spelling of 31425661 in words is "thirty-one million, four hundred twenty-five thousand, six hundred sixty-one".