21652601 has 4 divisors (see below), whose sum is σ = 22351104. Its totient is φ = 20954100.

The previous prime is 21652537. The next prime is 21652639. The reversal of 21652601 is 10625612.

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 21652601 - 2⁶ = 21652537 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (21652661) 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, 349205 + ... + 349266.

It is an arithmetic number, because the mean of its divisors is an integer number (5587776).

Almost surely, 2^21652601 is an apocalyptic number.

It is an amenable number.

21652601 is a deficient number, since it is larger than the sum of its proper divisors (698503).

21652601 is an equidigital number, since it uses as much as digits as its factorization.

21652601 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 698502.

The product of its (nonzero) digits is 720, while the sum is 23.

The square root of 21652601 is about 4653.2355409973. The cubic root of 21652601 is about 278.7212136213.

The spelling of 21652601 in words is "twenty-one million, six hundred fifty-two thousand, six hundred one".