21049665458 has 16 divisors (see below), whose sum is σ = 33165507456. Its totient is φ = 10000557600.

The previous prime is 21049665443. The next prime is 21049665479. The reversal of 21049665458 is 85456694012.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1508291 + ... + 1522182.

It is an arithmetic number, because the mean of its divisors is an integer number (2072844216).

Almost surely, 2^21049665458 is an apocalyptic number.

21049665458 is a deficient number, since it is larger than the sum of its proper divisors (12115841998).

21049665458 is a wasteful number, since it uses less digits than its factorization.

21049665458 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3030649.

The product of its (nonzero) digits is 2073600, while the sum is 50.

The spelling of 21049665458 in words is "twenty-one billion, forty-nine million, six hundred sixty-five thousand, four hundred fifty-eight".