21250612066540 has 24 divisors (see below), whose sum is σ = 46975037200560. Its totient is φ = 8052863519808.

The previous prime is 21250612066529. The next prime is 21250612066553. The reversal of 21250612066540 is 4566021605212.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 21250612066493 and 21250612066502.

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, 27961331287 + ... + 27961332046.

It is an arithmetic number, because the mean of its divisors is an integer number (1957293216690).

Almost surely, 2^{21250612066540} is an apocalyptic number.

21250612066540 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21250612066540 is an abundant number, since it is smaller than the sum of its proper divisors (25724425134020).

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

21250612066540 is a wasteful number, since it uses less digits than its factorization.

21250612066540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 55922663361 (or 55922663359 counting only the distinct ones).

The product of its (nonzero) digits is 172800, while the sum is 40.

The spelling of 21250612066540 in words is "twenty-one trillion, two hundred fifty billion, six hundred twelve million, sixty-six thousand, five hundred forty".