21912670 has 16 divisors (see below), whose sum is σ = 42477120. Its totient is φ = 8090784.

The previous prime is 21912623. The next prime is 21912673. The reversal of 21912670 is 7621912.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21912673) 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, 84150 + ... + 84409.

It is an arithmetic number, because the mean of its divisors is an integer number (2654820).

Almost surely, 2^21912670 is an apocalyptic number.

21912670 is a deficient number, since it is larger than the sum of its proper divisors (20564450).

21912670 is a wasteful number, since it uses less digits than its factorization.

21912670 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 168579.

The product of its (nonzero) digits is 1512, while the sum is 28.

The square root of 21912670 is about 4681.0970936309. The cubic root of 21912670 is about 279.8326806473.

The spelling of 21912670 in words is "twenty-one million, nine hundred twelve thousand, six hundred seventy".