21934857 has 8 divisors (see below), whose sum is σ = 33424576. Its totient is φ = 12534192.

The previous prime is 21934849. The next prime is 21934889. The reversal of 21934857 is 75843912.

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

It is not a de Polignac number, because 21934857 - 2³ = 21934849 is a prime.

It is a super-2 number, since 2×21934857² = 962275903220898, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21934837) 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, 522238 + ... + 522279.

It is an arithmetic number, because the mean of its divisors is an integer number (4178072).

Almost surely, 2^21934857 is an apocalyptic number.

It is an amenable number.

21934857 is a deficient number, since it is larger than the sum of its proper divisors (11489719).

21934857 is a wasteful number, since it uses less digits than its factorization.

21934857 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1044527.

The product of its digits is 60480, while the sum is 39.

The square root of 21934857 is about 4683.4663444931. The cubic root of 21934857 is about 279.9270941138.

It can be divided in two parts, 21934 and 857, that added together give a triangular number (22791 = T₂₁₃).

The spelling of 21934857 in words is "twenty-one million, nine hundred thirty-four thousand, eight hundred fifty-seven".