21069040 has 40 divisors (see below), whose sum is σ = 49246848. Its totient is φ = 8382720.

The previous prime is 21069031. The next prime is 21069073. The reversal of 21069040 is 4096012.

It is a tau number, because it is divible by the number of its divisors (40).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 17250 + ... + 18430.

Almost surely, 2^21069040 is an apocalyptic number.

21069040 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21069040 is an abundant number, since it is smaller than the sum of its proper divisors (28177808).

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

21069040 is a wasteful number, since it uses less digits than its factorization.

21069040 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1417 (or 1411 counting only the distinct ones).

The product of its (nonzero) digits is 432, while the sum is 22.

The square root of 21069040 is about 4590.1023953720. The cubic root of 21069040 is about 276.1944299681.

The spelling of 21069040 in words is "twenty-one million, sixty-nine thousand, forty".