21625601 has 8 divisors (see below), whose sum is σ = 21944544. Its totient is φ = 21309120.

The previous prime is 21625577. The next prime is 21625607. The reversal of 21625601 is 10652612.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21625601 is a prime.

It is a super-2 number, since 2×21625601² = 935333237222402, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21625607) 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, 23390 + ... + 24296.

It is an arithmetic number, because the mean of its divisors is an integer number (2743068).

Almost surely, 2^21625601 is an apocalyptic number.

It is an amenable number.

21625601 is a deficient number, since it is larger than the sum of its proper divisors (318943).

21625601 is a wasteful number, since it uses less digits than its factorization.

21625601 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1231.

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

The square root of 21625601 is about 4650.3334289059. Note that the first 3 decimals coincide. The cubic root of 21625601 is about 278.6053137203.

The spelling of 21625601 in words is "twenty-one million, six hundred twenty-five thousand, six hundred one".