21231101031 has 8 divisors (see below), whose sum is σ = 32352153984. Its totient is φ = 12132057720.

The previous prime is 21231101009. The next prime is 21231101069. The reversal of 21231101031 is 13010113212.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 21231101031 - 2⁶ = 21231100967 is a prime.

It is a super-2 number, since 2×21231101031² (a number of 21 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 21231101031.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21231101071) 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 7 ways as a sum of consecutive naturals, for example, 505502385 + ... + 505502426.

It is an arithmetic number, because the mean of its divisors is an integer number (4044019248).

Almost surely, 2^21231101031 is an apocalyptic number.

21231101031 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

21231101031 is a deficient number, since it is larger than the sum of its proper divisors (11121052953).

21231101031 is a wasteful number, since it uses less digits than its factorization.

21231101031 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1011004821.

The product of its (nonzero) digits is 36, while the sum is 15.

Adding to 21231101031 its reverse (13010113212), we get a palindrome (34241214243).

The spelling of 21231101031 in words is "twenty-one billion, two hundred thirty-one million, one hundred one thousand, thirty-one".