13530555621 has 48 divisors (see below), whose sum is σ = 22552912512. Its totient is φ = 7736256000.

The previous prime is 13530555617. The next prime is 13530555683. The reversal of 13530555621 is 12655503531.

13530555621 is a `hidden beast` number, since 1 + 3 + 530 + 55 + 56 + 21 = 666.

It is not a de Polignac number, because 13530555621 - 2² = 13530555617 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (13530555611) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 125521 + ... + 206921.

It is an arithmetic number, because the mean of its divisors is an integer number (469852344).

Almost surely, 2^13530555621 is an apocalyptic number.

13530555621 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

13530555621 is a deficient number, since it is larger than the sum of its proper divisors (9022356891).

13530555621 is a wasteful number, since it uses less digits than its factorization.

13530555621 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 81514 (or 81511 counting only the distinct ones).

The product of its (nonzero) digits is 67500, while the sum is 36.

The spelling of 13530555621 in words is "thirteen billion, five hundred thirty million, five hundred fifty-five thousand, six hundred twenty-one".