21354544607651 has 16 divisors (see below), whose sum is σ = 23137096752000. Its totient is φ = 19630504752768.

The previous prime is 21354544607633. The next prime is 21354544607659. The reversal of 21354544607651 is 15670644545312.

It is a cyclic number.

It is not a de Polignac number, because 21354544607651 - 2¹⁰ = 21354544606627 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21354544607593 and 21354544607602.

It is not an unprimeable number, because it can be changed into a prime (21354544607659) 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, 31077800 + ... + 31757498.

It is an arithmetic number, because the mean of its divisors is an integer number (1446068547000).

Almost surely, 2^{21354544607651} is an apocalyptic number.

21354544607651 is a deficient number, since it is larger than the sum of its proper divisors (1782552144349).

21354544607651 is a wasteful number, since it uses less digits than its factorization.

21354544607651 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 722738.

The product of its (nonzero) digits is 12096000, while the sum is 53.

The spelling of 21354544607651 in words is "twenty-one trillion, three hundred fifty-four billion, five hundred forty-four million, six hundred seven thousand, six hundred fifty-one".