21590042900 has 36 divisors (see below), whose sum is σ = 47734374492. Its totient is φ = 8473071360.

The previous prime is 21590042899. The next prime is 21590042909. The reversal of 21590042900 is 924009512.

It can be written as a sum of positive squares in 6 ways, for example, as 90859024 + 21499183876 = 9532^2 + 146626^2 .

It is a super-2 number, since 2×21590042900² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21590042909) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 2031497 + ... + 2042096.

It is an arithmetic number, because the mean of its divisors is an integer number (1325954847).

Almost surely, 2^21590042900 is an apocalyptic number.

21590042900 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21590042900 is an abundant number, since it is smaller than the sum of its proper divisors (26144331592).

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

21590042900 is a wasteful number, since it uses less digits than its factorization.

21590042900 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4073660 (or 4073653 counting only the distinct ones).

The product of its (nonzero) digits is 6480, while the sum is 32.

The spelling of 21590042900 in words is "twenty-one billion, five hundred ninety million, forty-two thousand, nine hundred".