31231220143243 has 16 divisors (see below), whose sum is σ = 31764821358816. Its totient is φ = 30698323626240.

The previous prime is 31231220143181. The next prime is 31231220143259. The reversal of 31231220143243 is 34234102213213.

It is a cyclic number.

It is not a de Polignac number, because 31231220143243 - 2¹⁷ = 31231220012171 is a prime.

It is a super-2 number, since 2×31231220143243² (a number of 28 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (31231220141243) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 555321921 + ... + 555378157.

It is an arithmetic number, because the mean of its divisors is an integer number (1985301334926).

Almost surely, 2^{31231220143243} is an apocalyptic number.

31231220143243 is a deficient number, since it is larger than the sum of its proper divisors (533601215573).

31231220143243 is a wasteful number, since it uses less digits than its factorization.

31231220143243 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 62334.

The product of its (nonzero) digits is 20736, while the sum is 31.

Adding to 31231220143243 its reverse (34234102213213), we get a palindrome (65465322356456).

The spelling of 31231220143243 in words is "thirty-one trillion, two hundred thirty-one billion, two hundred twenty million, one hundred forty-three thousand, two hundred forty-three".