21507045545 has 16 divisors (see below), whose sum is σ = 26073109440. Its totient is φ = 17029320000.

The previous prime is 21507045523. The next prime is 21507045577. The reversal of 21507045545 is 54554070512.

It is not a de Polignac number, because 21507045545 - 2⁶ = 21507045481 is a prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 21507045499 and 21507045508.

It is an unprimeable number.

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 15 ways as a sum of consecutive naturals, for example, 1939226 + ... + 1950284.

It is an arithmetic number, because the mean of its divisors is an integer number (1629569340).

Almost surely, 2^21507045545 is an apocalyptic number.

It is an amenable number.

21507045545 is a deficient number, since it is larger than the sum of its proper divisors (4566063895).

21507045545 is a wasteful number, since it uses less digits than its factorization.

21507045545 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15016.

The product of its (nonzero) digits is 140000, while the sum is 38.

The spelling of 21507045545 in words is "twenty-one billion, five hundred seven million, forty-five thousand, five hundred forty-five".