21132343531 has 8 divisors (see below), whose sum is σ = 23492034944. Its totient is φ = 18877527360.

The previous prime is 21132343523. The next prime is 21132343537. The reversal of 21132343531 is 13534323112.

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

It is a cyclic number.

It is not a de Polignac number, because 21132343531 - 2³ = 21132343523 is a prime.

It is a super-2 number, since 2×21132343531² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21132343531.

It is not an unprimeable number, because it can be changed into a prime (21132343537) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 26218386 + ... + 26219191.

It is an arithmetic number, because the mean of its divisors is an integer number (2936504368).

Almost surely, 2^21132343531 is an apocalyptic number.

21132343531 is a deficient number, since it is larger than the sum of its proper divisors (2359691413).

21132343531 is a wasteful number, since it uses less digits than its factorization.

21132343531 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 52437621.

The product of its digits is 6480, while the sum is 28.

Adding to 21132343531 its reverse (13534323112), we get a palindrome (34666666643).

The spelling of 21132343531 in words is "twenty-one billion, one hundred thirty-two million, three hundred forty-three thousand, five hundred thirty-one".