21722670 has 24 divisors (see below), whose sum is σ = 56479176. Its totient is φ = 5792688.

The previous prime is 21722647. The next prime is 21722671. The reversal of 21722670 is 7622712.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21722671) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 120592 + ... + 120771.

It is an arithmetic number, because the mean of its divisors is an integer number (2353299).

Almost surely, 2^21722670 is an apocalyptic number.

21722670 is an abundant number, since it is smaller than the sum of its proper divisors (34756506).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21722670 is a wasteful number, since it uses less digits than its factorization.

21722670 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 241376 (or 241373 counting only the distinct ones).

The product of its (nonzero) digits is 2352, while the sum is 27.

The square root of 21722670 is about 4660.7585219576. The cubic root of 21722670 is about 279.0215422531.

The spelling of 21722670 in words is "twenty-one million, seven hundred twenty-two thousand, six hundred seventy".