21715019452 has 12 divisors (see below), whose sum is σ = 43430038960. Its totient is φ = 9306436896.

The previous prime is 21715019441. The next prime is 21715019453. The reversal of 21715019452 is 25491051712.

21715019452 is an admirable number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21715019453) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 387768177 + ... + 387768232.

Almost surely, 2^21715019452 is an apocalyptic number.

It is an amenable number.

21715019452 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

21715019452 is a wasteful number, since it uses less digits than its factorization.

21715019452 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 775536420 (or 775536418 counting only the distinct ones).

The product of its (nonzero) digits is 25200, while the sum is 37.

The spelling of 21715019452 in words is "twenty-one billion, seven hundred fifteen million, nineteen thousand, four hundred fifty-two".