21165559374 has 8 divisors (see below), whose sum is σ = 42331118760. Its totient is φ = 7055186456.

The previous prime is 21165559369. The next prime is 21165559417. The reversal of 21165559374 is 47395556112.

It is a sphenic number, since it is the product of 3 distinct primes.

21165559374 is an admirable number.

It is a super-2 number, since 2×21165559374² (a number of 21 digits) contains 22 as substring.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1763796609 + ... + 1763796620.

It is an arithmetic number, because the mean of its divisors is an integer number (5291389845).

Almost surely, 2^21165559374 is an apocalyptic number.

21165559374 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21165559374 is a wasteful number, since it uses less digits than its factorization.

21165559374 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3527593234.

The product of its digits is 1134000, while the sum is 48.

The spelling of 21165559374 in words is "twenty-one billion, one hundred sixty-five million, five hundred fifty-nine thousand, three hundred seventy-four".