21012033131 has 4 divisors (see below), whose sum is σ = 21015483264. Its totient is φ = 21008583000.

The previous prime is 21012033109. The next prime is 21012033179. The reversal of 21012033131 is 13133021012.

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 21012033131 - 2¹⁸ = 21011770987 is a prime.

It is a super-2 number, since 2×21012033131² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21012033181) 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, 1715915 + ... + 1728116.

It is an arithmetic number, because the mean of its divisors is an integer number (5253870816).

Almost surely, 2^21012033131 is an apocalyptic number.

21012033131 is a deficient number, since it is larger than the sum of its proper divisors (3450133).

21012033131 is an equidigital number, since it uses as much as digits as its factorization.

21012033131 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3450132.

The product of its (nonzero) digits is 108, while the sum is 17.

Adding to 21012033131 its reverse (13133021012), we get a palindrome (34145054143).

The spelling of 21012033131 in words is "twenty-one billion, twelve million, thirty-three thousand, one hundred thirty-one".