21302123031 has 12 divisors (see below), whose sum is σ = 35165409552. Its totient is φ = 12172641696.

The previous prime is 21302123021. The next prime is 21302123053. The reversal of 21302123031 is 13032120312.

It is not a de Polignac number, because 21302123031 - 2⁷ = 21302122903 is a prime.

It is a super-2 number, since 2×21302123031² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21302122995 and 21302123013.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21302123021) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 169064406 + ... + 169064531.

It is an arithmetic number, because the mean of its divisors is an integer number (2930450796).

Almost surely, 2^21302123031 is an apocalyptic number.

21302123031 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

21302123031 is a deficient number, since it is larger than the sum of its proper divisors (13863286521).

21302123031 is a wasteful number, since it uses less digits than its factorization.

21302123031 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 338128950 (or 338128947 counting only the distinct ones).

The product of its (nonzero) digits is 216, while the sum is 18.

Adding to 21302123031 its reverse (13032120312), we get a palindrome (34334243343).

The spelling of 21302123031 in words is "twenty-one billion, three hundred two million, one hundred twenty-three thousand, thirty-one".