21146500 has 24 divisors (see below), whose sum is σ = 46185048. Its totient is φ = 8458400.

The previous prime is 21146399. The next prime is 21146501. The reversal of 21146500 is 564112.

It can be written as a sum of positive squares in 4 ways, for example, as 2414916 + 18731584 = 1554^2 + 4328^2 .

It is not an unprimeable number, because it can be changed into a prime (21146501) 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, 20647 + ... + 21646.

It is an arithmetic number, because the mean of its divisors is an integer number (1924377).

Almost surely, 2^21146500 is an apocalyptic number.

21146500 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21146500 is an abundant number, since it is smaller than the sum of its proper divisors (25038548).

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

21146500 is a wasteful number, since it uses less digits than its factorization.

21146500 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 42312 (or 42300 counting only the distinct ones).

The product of its (nonzero) digits is 240, while the sum is 19.

The square root of 21146500 is about 4598.5323745734. The cubic root of 21146500 is about 276.5324908654.

The spelling of 21146500 in words is "twenty-one million, one hundred forty-six thousand, five hundred".