21342581531 has 8 divisors (see below), whose sum is σ = 21665227584. Its totient is φ = 21020056200.

The previous prime is 21342581483. The next prime is 21342581537. The reversal of 21342581531 is 13518524312.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21342581531 is a prime.

It is a super-2 number, since 2×21342581531² (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 = 21342581491 and 21342581500.

It is not an unprimeable number, because it can be changed into a prime (21342581537) 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, 364796 + ... + 419238.

It is an arithmetic number, because the mean of its divisors is an integer number (2708153448).

Almost surely, 2^21342581531 is an apocalyptic number.

21342581531 is a deficient number, since it is larger than the sum of its proper divisors (322646053).

21342581531 is an equidigital number, since it uses as much as digits as its factorization.

21342581531 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 60361.

The product of its digits is 28800, while the sum is 35.

The spelling of 21342581531 in words is "twenty-one billion, three hundred forty-two million, five hundred eighty-one thousand, five hundred thirty-one".