21521502134 has 48 divisors (see below), whose sum is σ = 36215378640. Its totient is φ = 9581457600.

The previous prime is 21521502133. The next prime is 21521502139. The reversal of 21521502134 is 43120512512.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21521502131) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 10400852 + ... + 10402920.

It is an arithmetic number, because the mean of its divisors is an integer number (754487055).

Almost surely, 2^21521502134 is an apocalyptic number.

21521502134 is a deficient number, since it is larger than the sum of its proper divisors (14693876506).

21521502134 is a wasteful number, since it uses less digits than its factorization.

21521502134 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2957 (or 2946 counting only the distinct ones).

The product of its (nonzero) digits is 2400, while the sum is 26.

The spelling of 21521502134 in words is "twenty-one billion, five hundred twenty-one million, five hundred two thousand, one hundred thirty-four".