21055450215 has 32 divisors (see below), whose sum is σ = 36255197376. Its totient is φ = 10395740160.

The previous prime is 21055450189. The next prime is 21055450237. The reversal of 21055450215 is 51205455012.

It is not a de Polignac number, because 21055450215 - 2¹² = 21055446119 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 661252 + ... + 692361.

It is an arithmetic number, because the mean of its divisors is an integer number (1132974918).

Almost surely, 2^21055450215 is an apocalyptic number.

21055450215 is a deficient number, since it is larger than the sum of its proper divisors (15199747161).

21055450215 is a wasteful number, since it uses less digits than its factorization.

21055450215 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1353699.

The product of its (nonzero) digits is 10000, while the sum is 30.

The spelling of 21055450215 in words is "twenty-one billion, fifty-five million, four hundred fifty thousand, two hundred fifteen".