31425421 has 4 divisors (see below), whose sum is σ = 31590144. Its totient is φ = 31260700.

The previous prime is 31425397. The next prime is 31425461. The reversal of 31425421 is 12452413.

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 31425421 - 2⁷ = 31425293 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 31425392 and 31425401.

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 3 ways as a sum of consecutive naturals, for example, 82075 + ... + 82456.

It is an arithmetic number, because the mean of its divisors is an integer number (7897536).

Almost surely, 2^31425421 is an apocalyptic number.

It is an amenable number.

31425421 is a deficient number, since it is larger than the sum of its proper divisors (164723).

31425421 is a wasteful number, since it uses less digits than its factorization.

31425421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 164722.

The product of its digits is 960, while the sum is 22.

The square root of 31425421 is about 5605.8381175343. The cubic root of 31425421 is about 315.5685407099.

Adding to 31425421 its reverse (12452413), we get a palindrome (43877834).

The spelling of 31425421 in words is "thirty-one million, four hundred twenty-five thousand, four hundred twenty-one".