21654546761 has 8 divisors (see below), whose sum is σ = 22431590400. Its totient is φ = 20879525520.

The previous prime is 21654546737. The next prime is 21654546763. The reversal of 21654546761 is 16764545612.

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-21654546761 is a prime.

It is a super-2 number, since 2×21654546761² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21654546763) 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, 483785 + ... + 526646.

It is an arithmetic number, because the mean of its divisors is an integer number (2803948800).

Almost surely, 2^21654546761 is an apocalyptic number.

It is an amenable number.

21654546761 is a deficient number, since it is larger than the sum of its proper divisors (777043639).

21654546761 is a wasteful number, since it uses less digits than its factorization.

21654546761 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1011199.

The product of its digits is 1209600, while the sum is 47.

The spelling of 21654546761 in words is "twenty-one billion, six hundred fifty-four million, five hundred forty-six thousand, seven hundred sixty-one".