21946900 has 36 divisors (see below), whose sum is σ = 50135680. Its totient is φ = 8316000.

The previous prime is 21946891. The next prime is 21946907. The reversal of 21946900 is 964912.

It is a happy number.

It is a super-2 number, since 2×21946900² = 963332839220000, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21946907) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 3876 + ... + 7675.

Almost surely, 2^21946900 is an apocalyptic number.

21946900 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21946900 is an abundant number, since it is smaller than the sum of its proper divisors (28188780).

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

21946900 is a wasteful number, since it uses less digits than its factorization.

21946900 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11584 (or 11577 counting only the distinct ones).

The product of its (nonzero) digits is 3888, while the sum is 31.

The square root of 21946900 is about 4684.7518610915. The cubic root of 21946900 is about 279.9783146471.

The spelling of 21946900 in words is "twenty-one million, nine hundred forty-six thousand, nine hundred".