21113211031 has 16 divisors (see below), whose sum is σ = 24068113920. Its totient is φ = 18333263520.

The previous prime is 21113211023. The next prime is 21113211073. The reversal of 21113211031 is 13011231112.

It is a happy number.

It is not a de Polignac number, because 21113211031 - 2³ = 21113211023 is a prime.

It is a super-2 number, since 2×21113211031² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21113210996 and 21113211014.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21113211131) 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, 120526 + ... + 238228.

It is an arithmetic number, because the mean of its divisors is an integer number (1504257120).

Almost surely, 2^21113211031 is an apocalyptic number.

21113211031 is a deficient number, since it is larger than the sum of its proper divisors (2954902889).

21113211031 is a wasteful number, since it uses less digits than its factorization.

21113211031 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 118446.

The product of its (nonzero) digits is 36, while the sum is 16.

Adding to 21113211031 its reverse (13011231112), we get a palindrome (34124442143).

The spelling of 21113211031 in words is "twenty-one billion, one hundred thirteen million, two hundred eleven thousand, thirty-one".