21073104 has 60 divisors (see below), whose sum is σ = 63517636. Its totient is φ = 6483456.

The previous prime is 21073103. The next prime is 21073127. The reversal of 21073104 is 40137012.

It can be written as a sum of positive squares in 2 ways, for example, as 10497600 + 10575504 = 3240^2 + 3252^2 .

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21073103) 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, 3757 + ... + 7500.

Almost surely, 2^21073104 is an apocalyptic number.

21073104 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

21073104 is an abundant number, since it is smaller than the sum of its proper divisors (42444532).

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

21073104 is a wasteful number, since it uses less digits than its factorization.

21073104 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11284 (or 11275 counting only the distinct ones).

The product of its (nonzero) digits is 168, while the sum is 18.

The square root of 21073104 is about 4590.5450656758. The cubic root of 21073104 is about 276.2121871765.

The spelling of 21073104 in words is "twenty-one million, seventy-three thousand, one hundred four".