21540053131 has 8 divisors (see below), whose sum is σ = 21645939744. Its totient is φ = 21434401920.

The previous prime is 21540053111. The next prime is 21540053251. The reversal of 21540053131 is 13135004512.

It is a happy number.

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 21540053131 - 2¹⁵ = 21540020363 is a prime.

It is a super-2 number, since 2×21540053131² (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 = 21540053096 and 21540053105.

It is not an unprimeable number, because it can be changed into a prime (21540053111) 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, 126025 + ... + 242821.

It is an arithmetic number, because the mean of its divisors is an integer number (2705742468).

Almost surely, 2^21540053131 is an apocalyptic number.

21540053131 is a deficient number, since it is larger than the sum of its proper divisors (105886613).

21540053131 is a wasteful number, since it uses less digits than its factorization.

21540053131 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 117701.

The product of its (nonzero) digits is 1800, while the sum is 25.

Adding to 21540053131 its reverse (13135004512), we get a palindrome (34675057643).

The spelling of 21540053131 in words is "twenty-one billion, five hundred forty million, fifty-three thousand, one hundred thirty-one".