21265016874 has 32 divisors (see below), whose sum is σ = 43408293120. Its totient is φ = 6942936000.

The previous prime is 21265016833. The next prime is 21265016879. The reversal of 21265016874 is 47861056212.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (21265016879) 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 in 15 ways as a sum of consecutive naturals, for example, 34077 + ... + 209024.

It is an arithmetic number, because the mean of its divisors is an integer number (1356509160).

Almost surely, 2^21265016874 is an apocalyptic number.

21265016874 is an abundant number, since it is smaller than the sum of its proper divisors (22143276246).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21265016874 is a wasteful number, since it uses less digits than its factorization.

21265016874 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 243406.

The product of its (nonzero) digits is 161280, while the sum is 42.

The spelling of 21265016874 in words is "twenty-one billion, two hundred sixty-five million, sixteen thousand, eight hundred seventy-four".