21021230031331 has 4 divisors (see below), whose sum is σ = 21172461902200. Its totient is φ = 20869998160464.

The previous prime is 21021230031317. The next prime is 21021230031353. The reversal of 21021230031331 is 13313003212012.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21021230031331 - 2¹³ = 21021230023139 is a prime.

It is a super-2 number, since 2×21021230031331² (a number of 27 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21021230031631) 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, 75615935226 + ... + 75615935503.

It is an arithmetic number, because the mean of its divisors is an integer number (5293115475550).

Almost surely, 2^{21021230031331} is an apocalyptic number.

21021230031331 is a deficient number, since it is larger than the sum of its proper divisors (151231870869).

21021230031331 is a wasteful number, since it uses less digits than its factorization.

21021230031331 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 151231870868.

The product of its (nonzero) digits is 648, while the sum is 22.

Adding to 21021230031331 its reverse (13313003212012), we get a palindrome (34334233243343).

The spelling of 21021230031331 in words is "twenty-one trillion, twenty-one billion, two hundred thirty million, thirty-one thousand, three hundred thirty-one".