21604462655 has 8 divisors (see below), whose sum is σ = 26154783792. Its totient is φ = 17130617728.

The previous prime is 21604462613. The next prime is 21604462657. The reversal of 21604462655 is 55626440612.

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 21604462655 - 2⁶ = 21604462591 is a prime.

It is a super-2 number, since 2×21604462655² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21604462657) 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, 19118429 + ... + 19119558.

It is an arithmetic number, because the mean of its divisors is an integer number (3269347974).

Almost surely, 2^21604462655 is an apocalyptic number.

21604462655 is a deficient number, since it is larger than the sum of its proper divisors (4550321137).

21604462655 is a wasteful number, since it uses less digits than its factorization.

21604462655 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 38238105.

The product of its (nonzero) digits is 345600, while the sum is 41.

The spelling of 21604462655 in words is "twenty-one billion, six hundred four million, four hundred sixty-two thousand, six hundred fifty-five".