21433891031 has 4 divisors (see below), whose sum is σ = 24495875472. Its totient is φ = 18371906592.

The previous prime is 21433891027. The next prime is 21433891103. The reversal of 21433891031 is 13019833412.

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 21433891031 - 2² = 21433891027 is a prime.

It is a super-2 number, since 2×21433891031² (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 = 21433890982 and 21433891000.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21433891001) 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, 1530992210 + ... + 1530992223.

It is an arithmetic number, because the mean of its divisors is an integer number (6123968868).

Almost surely, 2^21433891031 is an apocalyptic number.

21433891031 is a deficient number, since it is larger than the sum of its proper divisors (3061984441).

21433891031 is an equidigital number, since it uses as much as digits as its factorization.

21433891031 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3061984440.

The product of its (nonzero) digits is 15552, while the sum is 35.

The spelling of 21433891031 in words is "twenty-one billion, four hundred thirty-three million, eight hundred ninety-one thousand, thirty-one".