31352421 has 4 divisors (see below), whose sum is σ = 41803232. Its totient is φ = 20901612.

The previous prime is 31352417. The next prime is 31352441. The reversal of 31352421 is 12425313.

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 not a de Polignac number, because 31352421 - 2² = 31352417 is a prime.

It is a super-2 number, since 2×31352421² = 1965948605122482, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31352441) 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, 5225401 + ... + 5225406.

It is an arithmetic number, because the mean of its divisors is an integer number (10450808).

Almost surely, 2^31352421 is an apocalyptic number.

It is an amenable number.

31352421 is a deficient number, since it is larger than the sum of its proper divisors (10450811).

31352421 is a wasteful number, since it uses less digits than its factorization.

31352421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10450810.

The product of its digits is 720, while the sum is 21.

The square root of 31352421 is about 5599.3232626809. The cubic root of 31352421 is about 315.3240002134.

Adding to 31352421 its reverse (12425313), we get a palindrome (43777734).

The spelling of 31352421 in words is "thirty-one million, three hundred fifty-two thousand, four hundred twenty-one".