21463554661 has 8 divisors (see below), whose sum is σ = 22160712704. Its totient is φ = 20766695760.

The previous prime is 21463554643. The next prime is 21463554727. The reversal of 21463554661 is 16645536412.

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 21463554661 - 2⁹ = 21463554149 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21463554461) 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, 75895 + ... + 220651.

It is an arithmetic number, because the mean of its divisors is an integer number (2770089088).

Almost surely, 2^21463554661 is an apocalyptic number.

It is an amenable number.

21463554661 is a deficient number, since it is larger than the sum of its proper divisors (697158043).

21463554661 is a wasteful number, since it uses less digits than its factorization.

21463554661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 149571.

The product of its digits is 518400, while the sum is 43.

The spelling of 21463554661 in words is "twenty-one billion, four hundred sixty-three million, five hundred fifty-four thousand, six hundred sixty-one".