21872659 has 8 divisors (see below), whose sum is σ = 23250240. Its totient is φ = 20505216.

The previous prime is 21872647. The next prime is 21872663. The reversal of 21872659 is 95627812.

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-21872659 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21872689) 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, 2182 + ... + 6964.

It is an arithmetic number, because the mean of its divisors is an integer number (2906280).

Almost surely, 2^21872659 is an apocalyptic number.

21872659 is a deficient number, since it is larger than the sum of its proper divisors (1377581).

21872659 is a wasteful number, since it uses less digits than its factorization.

21872659 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5069.

The product of its digits is 60480, while the sum is 40.

The square root of 21872659 is about 4676.8214633445. The cubic root of 21872659 is about 279.6622585899.

The spelling of 21872659 in words is "twenty-one million, eight hundred seventy-two thousand, six hundred fifty-nine".