21477142561 has 8 divisors (see below), whose sum is σ = 25612493184. Its totient is φ = 17608588800.

The previous prime is 21477142501. The next prime is 21477142579. The reversal of 21477142561 is 16524177412.

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 21477142561 - 2³¹ = 19329658913 is a prime.

It is a super-2 number, since 2×21477142561² (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 (21477142501) 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, 66699040 + ... + 66699361.

It is an arithmetic number, because the mean of its divisors is an integer number (3201561648).

Almost surely, 2^21477142561 is an apocalyptic number.

It is an amenable number.

21477142561 is a deficient number, since it is larger than the sum of its proper divisors (4135350623).

21477142561 is a wasteful number, since it uses less digits than its factorization.

21477142561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 133398431.

The product of its digits is 94080, while the sum is 40.

The spelling of 21477142561 in words is "twenty-one billion, four hundred seventy-seven million, one hundred forty-two thousand, five hundred sixty-one".