21550530131 has 16 divisors (see below), whose sum is σ = 24621861600. Its totient is φ = 18685751808.

The previous prime is 21550530073. The next prime is 21550530137. The reversal of 21550530131 is 13103505512.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 21550530131 - 2¹⁸ = 21550267987 is a prime.

It is a super-2 number, since 2×21550530131² (a number of 21 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 21550530131.

It is not an unprimeable number, because it can be changed into a prime (21550530137) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 16700 + ... + 208278.

It is an arithmetic number, because the mean of its divisors is an integer number (1538866350).

Almost surely, 2^21550530131 is an apocalyptic number.

21550530131 is a deficient number, since it is larger than the sum of its proper divisors (3071331469).

21550530131 is a wasteful number, since it uses less digits than its factorization.

21550530131 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 192118.

The product of its (nonzero) digits is 2250, while the sum is 26.

The spelling of 21550530131 in words is "twenty-one billion, five hundred fifty million, five hundred thirty thousand, one hundred thirty-one".