21187010 has 32 divisors (see below), whose sum is σ = 41610240. Its totient is φ = 7720128.

The previous prime is 21186983. The next prime is 21187013. The reversal of 21187010 is 1078112.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (21187013) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 9239 + ... + 11301.

It is an arithmetic number, because the mean of its divisors is an integer number (1300320).

Almost surely, 2^21187010 is an apocalyptic number.

21187010 is a deficient number, since it is larger than the sum of its proper divisors (20423230).

21187010 is a wasteful number, since it uses less digits than its factorization.

21187010 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2162.

The product of its (nonzero) digits is 112, while the sum is 20.

The square root of 21187010 is about 4602.9349332790. The cubic root of 21187010 is about 276.7089611313.

The spelling of 21187010 in words is "twenty-one million, one hundred eighty-seven thousand, ten".