21004550415 has 24 divisors (see below), whose sum is σ = 36868752960. Its totient is φ = 11060622144.

The previous prime is 21004550377. The next prime is 21004550467. The reversal of 21004550415 is 51405540012.

21004550415 is a `hidden beast` number, since 2 + 100 + 4 + 550 + 4 + 1 + 5 = 666.

It is not a de Polignac number, because 21004550415 - 2⁸ = 21004550159 is a prime.

It is a super-2 number, since 2×21004550415² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 2950672 + ... + 2957781.

It is an arithmetic number, because the mean of its divisors is an integer number (1536198040).

Almost surely, 2^21004550415 is an apocalyptic number.

21004550415 is a deficient number, since it is larger than the sum of its proper divisors (15864202545).

21004550415 is a wasteful number, since it uses less digits than its factorization.

21004550415 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5908543 (or 5908540 counting only the distinct ones).

The product of its (nonzero) digits is 4000, while the sum is 27.

The spelling of 21004550415 in words is "twenty-one billion, four million, five hundred fifty thousand, four hundred fifteen".