31648231 has 2 divisors, whose sum is σ = 31648232. Its totient is φ = 31648230.

The previous prime is 31648229. The next prime is 31648277. The reversal of 31648231 is 13284613.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 31648231 - 2¹ = 31648229 is a prime.

It is a super-3 number, since 3×31648231³ (a number of 23 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

Together with 31648229, it forms a pair of twin primes.

It is equal to p_1953424 and since 31648231 and 1953424 have the same sum of digits, it is a Honaker prime.

It is a self number, because there is not a number n which added to its sum of digits gives 31648231.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (31648291) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15824115 + 15824116.

It is an arithmetic number, because the mean of its divisors is an integer number (15824116).

Almost surely, 2^31648231 is an apocalyptic number.

31648231 is a deficient number, since it is larger than the sum of its proper divisors (1).

31648231 is an equidigital number, since it uses as much as digits as its factorization.

31648231 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3456, while the sum is 28.

The square root of 31648231 is about 5625.6760482630. The cubic root of 31648231 is about 316.3125912556.

The spelling of 31648231 in words is "thirty-one million, six hundred forty-eight thousand, two hundred thirty-one".