21037554 has 24 divisors (see below), whose sum is σ = 46055100. Its totient is φ = 6939648.

The previous prime is 21037537. The next prime is 21037559. The reversal of 21037554 is 45573012.

It is a happy number.

21037554 is a `hidden beast` number, since 2 + 103 + 7 + 554 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 20930625 + 106929 = 4575^2 + 327^2 .

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (21037559) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 4279 + ... + 7770.

Almost surely, 2^21037554 is an apocalyptic number.

21037554 is an abundant number, since it is smaller than the sum of its proper divisors (25017546).

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

21037554 is a wasteful number, since it uses less digits than its factorization.

21037554 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12154 (or 12151 counting only the distinct ones).

The product of its (nonzero) digits is 4200, while the sum is 27.

The square root of 21037554 is about 4586.6713420519. The cubic root of 21037554 is about 276.0567778590.

The spelling of 21037554 in words is "twenty-one million, thirty-seven thousand, five hundred fifty-four".