21607601 has 4 divisors (see below), whose sum is σ = 21628992. Its totient is φ = 21586212.

The previous prime is 21607591. The next prime is 21607613. The reversal of 21607601 is 10670612.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 21607601 - 2¹⁴ = 21591217 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21607661) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9101 + ... + 11226.

It is an arithmetic number, because the mean of its divisors is an integer number (5407248).

Almost surely, 2^21607601 is an apocalyptic number.

It is an amenable number.

21607601 is a deficient number, since it is larger than the sum of its proper divisors (21391).

21607601 is a wasteful number, since it uses less digits than its factorization.

21607601 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21390.

The product of its (nonzero) digits is 504, while the sum is 23.

The square root of 21607601 is about 4648.3976809219. The cubic root of 21607601 is about 278.5279935160.

The spelling of 21607601 in words is "twenty-one million, six hundred seven thousand, six hundred one".