21166488 has 64 divisors (see below), whose sum is σ = 67200000. Its totient is φ = 6047136.

The previous prime is 21166487. The next prime is 21166489. The reversal of 21166488 is 88466112.

21166488 is a `hidden beast` number, since 2 + 1 + 1 + 6 + 648 + 8 = 666.

It is an interprime number because it is at equal distance from previous prime (21166487) and next prime (21166489).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a nude number because it is divisible by every one of its digits.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21166487) 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, 5488 + ... + 8511.

It is an arithmetic number, because the mean of its divisors is an integer number (1050000).

Almost surely, 2^21166488 is an apocalyptic number.

21166488 is a gapful number since it is divisible by the number (28) formed by its first and last digit.

It is an amenable number.

21166488 is an abundant number, since it is smaller than the sum of its proper divisors (46033512).

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

21166488 is a wasteful number, since it uses less digits than its factorization.

21166488 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14021 (or 14011 counting only the distinct ones).

The product of its digits is 18432, while the sum is 36.

The square root of 21166488 is about 4600.7051633418. The cubic root of 21166488 is about 276.6195910291.

The spelling of 21166488 in words is "twenty-one million, one hundred sixty-six thousand, four hundred eighty-eight".