31387406173 has 4 divisors (see below), whose sum is σ = 31390876960. Its totient is φ = 31383935388.

The previous prime is 31387406137. The next prime is 31387406201. The reversal of 31387406173 is 37160478313.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 31387406173 - 2¹³ = 31387397981 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 (31387406273) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1721793 + ... + 1739926.

It is an arithmetic number, because the mean of its divisors is an integer number (7847719240).

Almost surely, 2^31387406173 is an apocalyptic number.

It is an amenable number.

31387406173 is a deficient number, since it is larger than the sum of its proper divisors (3470787).

31387406173 is an equidigital number, since it uses as much as digits as its factorization.

31387406173 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3470786.

The product of its (nonzero) digits is 254016, while the sum is 43.

The spelling of 31387406173 in words is "thirty-one billion, three hundred eighty-seven million, four hundred six thousand, one hundred seventy-three".