8921205715 has 4 divisors (see below), whose sum is σ = 10705446864. Its totient is φ = 7136964568.

The previous prime is 8921205701. The next prime is 8921205731. The reversal of 8921205715 is 5175021298.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 8921205715 - 2¹⁵ = 8921172947 is a prime.

It is a super-2 number, since 2×8921205715² (a number of 21 digits) contains 22 as substring.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 892120567 + ... + 892120576.

It is an arithmetic number, because the mean of its divisors is an integer number (2676361716).

Almost surely, 2^8921205715 is an apocalyptic number.

8921205715 is a deficient number, since it is larger than the sum of its proper divisors (1784241149).

8921205715 is a wasteful number, since it uses less digits than its factorization.

8921205715 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1784241148.

The product of its (nonzero) digits is 50400, while the sum is 40.

The square root of 8921205715 is about 94452.1345179663. The cubic root of 8921205715 is about 2073.9956984444.

The spelling of 8921205715 in words is "eight billion, nine hundred twenty-one million, two hundred five thousand, seven hundred fifteen".