21003540100 has 36 divisors (see below), whose sum is σ = 46126828944. Its totient is φ = 8300190880.

The previous prime is 21003540097. The next prime is 21003540113. The reversal of 21003540100 is 104530012.

It is a super-2 number, since 2×21003540100² (a number of 21 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1256974 + ... + 1273573.

It is an arithmetic number, because the mean of its divisors is an integer number (1281300804).

Almost surely, 2^21003540100 is an apocalyptic number.

21003540100 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21003540100 is an abundant number, since it is smaller than the sum of its proper divisors (25123288844).

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

21003540100 is a wasteful number, since it uses less digits than its factorization.

21003540100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2530644 (or 2530637 counting only the distinct ones).

The product of its (nonzero) digits is 120, while the sum is 16.

The spelling of 21003540100 in words is "twenty-one billion, three million, five hundred forty thousand, one hundred".