31221342243 has 32 divisors (see below), whose sum is σ = 56927808000. Its totient is φ = 16468399008.

The previous prime is 31221342227. The next prime is 31221342253. The reversal of 31221342243 is 34224312213.

31221342243 is a `hidden beast` number, since 312 + 2 + 1 + 342 + 2 + 4 + 3 = 666.

It is not a de Polignac number, because 31221342243 - 2⁴ = 31221342227 is a prime.

It is a super-2 number, since 2×31221342243² (a number of 22 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is not an unprimeable number, because it can be changed into a prime (31221342223) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 6351093 + ... + 6356006.

It is an arithmetic number, because the mean of its divisors is an integer number (1778994000).

Almost surely, 2^31221342243 is an apocalyptic number.

31221342243 is a deficient number, since it is larger than the sum of its proper divisors (25706465757).

31221342243 is a wasteful number, since it uses less digits than its factorization.

31221342243 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12707128 (or 12707122 counting only the distinct ones).

The product of its digits is 6912, while the sum is 27.

Adding to 31221342243 its reverse (34224312213), we get a palindrome (65445654456).

The spelling of 31221342243 in words is "thirty-one billion, two hundred twenty-one million, three hundred forty-two thousand, two hundred forty-three".