21519099 has 24 divisors (see below), whose sum is σ = 37070592. Its totient is φ = 11761200.

The previous prime is 21519083. The next prime is 21519101. The reversal of 21519099 is 99091512.

It is not a de Polignac number, because 21519099 - 2⁴ = 21519083 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21519079) 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, 5977 + ... + 8874.

It is an arithmetic number, because the mean of its divisors is an integer number (1544608).

Almost surely, 2^21519099 is an apocalyptic number.

21519099 is a deficient number, since it is larger than the sum of its proper divisors (15551493).

21519099 is a wasteful number, since it uses less digits than its factorization.

21519099 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14887 (or 14884 counting only the distinct ones).

The product of its (nonzero) digits is 7290, while the sum is 36.

The square root of 21519099 is about 4638.8682887101. The cubic root of 21519099 is about 278.1472013418.

The spelling of 21519099 in words is "twenty-one million, five hundred nineteen thousand, ninety-nine".