31621310243 has 2 divisors, whose sum is σ = 31621310244. Its totient is φ = 31621310242.

The previous prime is 31621310137. The next prime is 31621310251. The reversal of 31621310243 is 34201312613.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 31621310243 - 2¹⁸ = 31621048099 is a prime.

It is a super-3 number, since 3×31621310243³ (a number of 32 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is not a weakly prime, because it can be changed into another prime (31621310543) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15810655121 + 15810655122.

It is an arithmetic number, because the mean of its divisors is an integer number (15810655122).

Almost surely, 2^31621310243 is an apocalyptic number.

31621310243 is a deficient number, since it is larger than the sum of its proper divisors (1).

31621310243 is an equidigital number, since it uses as much as digits as its factorization.

31621310243 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2592, while the sum is 26.

Adding to 31621310243 its reverse (34201312613), we get a palindrome (65822622856).

The spelling of 31621310243 in words is "thirty-one billion, six hundred twenty-one million, three hundred ten thousand, two hundred forty-three".