21473556161 has 16 divisors (see below), whose sum is σ = 22767117120. Its totient is φ = 20229518400.

The previous prime is 21473556133. The next prime is 21473556197. The reversal of 21473556161 is 16165537412.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 21473556161 - 2¹⁴ = 21473539777 is a prime.

It is a super-2 number, since 2×21473556161² (a number of 21 digits) contains 22 as substring.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (21473556121) 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, 54611 + ... + 214311.

It is an arithmetic number, because the mean of its divisors is an integer number (1422944820).

Almost surely, 2^21473556161 is an apocalyptic number.

It is an amenable number.

21473556161 is a deficient number, since it is larger than the sum of its proper divisors (1293560959).

21473556161 is a wasteful number, since it uses less digits than its factorization.

21473556161 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 159856.

The product of its digits is 151200, while the sum is 41.

The spelling of 21473556161 in words is "twenty-one billion, four hundred seventy-three million, five hundred fifty-six thousand, one hundred sixty-one".