21063909715 has 8 divisors (see below), whose sum is σ = 25381575648. Its totient is φ = 16781205120.

The previous prime is 21063909697. The next prime is 21063909719. The reversal of 21063909715 is 51790936012.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 21063909715 - 2²³ = 21055521107 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21063909719) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 8739007 + ... + 8741416.

It is an arithmetic number, because the mean of its divisors is an integer number (3172696956).

Almost surely, 2^21063909715 is an apocalyptic number.

21063909715 is a deficient number, since it is larger than the sum of its proper divisors (4317665933).

21063909715 is a wasteful number, since it uses less digits than its factorization.

21063909715 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17480669.

The product of its (nonzero) digits is 102060, while the sum is 43.

The spelling of 21063909715 in words is "twenty-one billion, sixty-three million, nine hundred nine thousand, seven hundred fifteen".