31928421 has 8 divisors (see below), whose sum is σ = 48652864. Its totient is φ = 18244800.

The previous prime is 31928401. The next prime is 31928441. The reversal of 31928421 is 12482913.

It is an interprime number because it is at equal distance from previous prime (31928401) and next prime (31928441).

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 31928421 - 2¹⁵ = 31895653 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 (31928401) 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 7 ways as a sum of consecutive naturals, for example, 760180 + ... + 760221.

It is an arithmetic number, because the mean of its divisors is an integer number (6081608).

Almost surely, 2^31928421 is an apocalyptic number.

It is an amenable number.

31928421 is a deficient number, since it is larger than the sum of its proper divisors (16724443).

31928421 is a wasteful number, since it uses less digits than its factorization.

31928421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1520411.

The product of its digits is 3456, while the sum is 30.

The square root of 31928421 is about 5650.5239580060. The cubic root of 31928421 is about 317.2433157989.

The spelling of 31928421 in words is "thirty-one million, nine hundred twenty-eight thousand, four hundred twenty-one".