21136610 has 64 divisors (see below), whose sum is σ = 44789760. Its totient is φ = 7096320.

The previous prime is 21136603. The next prime is 21136613. The reversal of 21136610 is 1663112.

It is not an unprimeable number, because it can be changed into a prime (21136613) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 166367 + ... + 166493.

It is an arithmetic number, because the mean of its divisors is an integer number (699840).

Almost surely, 2^21136610 is an apocalyptic number.

21136610 is an abundant number, since it is smaller than the sum of its proper divisors (23653150).

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

21136610 is a wasteful number, since it uses less digits than its factorization.

21136610 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 251.

The product of its (nonzero) digits is 216, while the sum is 20.

The square root of 21136610 is about 4597.4569057252. The cubic root of 21136610 is about 276.4893736781.

Adding to 21136610 its reverse (1663112), we get a palindrome (22799722).

It can be divided in two parts, 21 and 136610, that added together give a palindrome (136631).

The spelling of 21136610 in words is "twenty-one million, one hundred thirty-six thousand, six hundred ten".