21131133430 has 32 divisors (see below), whose sum is σ = 41503891968. Its totient is φ = 7682191200.

The previous prime is 21131133349. The next prime is 21131133449. The reversal of 21131133430 is 3433113112.

It is a Harshad number since it is a multiple of its sum of digits (22).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 484089 + ... + 525931.

It is an arithmetic number, because the mean of its divisors is an integer number (1296996624).

Almost surely, 2^21131133430 is an apocalyptic number.

21131133430 is a deficient number, since it is larger than the sum of its proper divisors (20372758538).

21131133430 is a wasteful number, since it uses less digits than its factorization.

21131133430 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 46452.

The product of its (nonzero) digits is 648, while the sum is 22.

Adding to 21131133430 its reverse (3433113112), we get a palindrome (24564246542).

The spelling of 21131133430 in words is "twenty-one billion, one hundred thirty-one million, one hundred thirty-three thousand, four hundred thirty".