31397477 has 4 divisors (see below), whose sum is σ = 31434156. Its totient is φ = 31360800.

The previous prime is 31397447. The next prime is 31397479. The reversal of 31397477 is 77479313.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 16273156 + 15124321 = 4034^2 + 3889^2 .

It is a cyclic number.

It is not a de Polignac number, because 31397477 - 2⁸ = 31397221 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 (31397479) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 17024 + ... + 18777.

It is an arithmetic number, because the mean of its divisors is an integer number (7858539).

Almost surely, 2^31397477 is an apocalyptic number.

It is an amenable number.

31397477 is a deficient number, since it is larger than the sum of its proper divisors (36679).

31397477 is an equidigital number, since it uses as much as digits as its factorization.

31397477 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 36678.

The product of its digits is 111132, while the sum is 41.

The square root of 31397477 is about 5603.3451615977. The cubic root of 31397477 is about 315.4749767300.

The spelling of 31397477 in words is "thirty-one million, three hundred ninety-seven thousand, four hundred seventy-seven".