21873700 has 18 divisors (see below), whose sum is σ = 47466146. Its totient is φ = 8749440.

The previous prime is 21873673. The next prime is 21873707. The reversal of 21873700 is 737812.

It is a happy number.

It can be written as a sum of positive squares in 3 ways, for example, as 195364 + 21678336 = 442^2 + 4656^2 .

It is not an unprimeable number, because it can be changed into a prime (21873707) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 109269 + ... + 109468.

Almost surely, 2^21873700 is an apocalyptic number.

21873700 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21873700 is an abundant number, since it is smaller than the sum of its proper divisors (25592446).

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

21873700 is a wasteful number, since it uses less digits than its factorization.

21873700 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 218751 (or 218744 counting only the distinct ones).

The product of its (nonzero) digits is 2352, while the sum is 28.

The square root of 21873700 is about 4676.9327555568. The cubic root of 21873700 is about 279.6666952368. Note that the first 4 decimals are identical.

The spelling of 21873700 in words is "twenty-one million, eight hundred seventy-three thousand, seven hundred".