21004512514 has 4 divisors (see below), whose sum is σ = 31506768774. Its totient is φ = 10502256256.

The previous prime is 21004512443. The next prime is 21004512517. The reversal of 21004512514 is 41521540012.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 20852804025 + 151708489 = 144405^2 + 12317^2 .

It is not an unprimeable number, because it can be changed into a prime (21004512517) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5251128127 + ... + 5251128130.

Almost surely, 2^21004512514 is an apocalyptic number.

21004512514 is a deficient number, since it is larger than the sum of its proper divisors (10502256260).

21004512514 is a wasteful number, since it uses less digits than its factorization.

21004512514 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10502256259.

The product of its (nonzero) digits is 1600, while the sum is 25.

The spelling of 21004512514 in words is "twenty-one billion, four million, five hundred twelve thousand, five hundred fourteen".