1913520817 has 4 divisors (see below), whose sum is σ = 2060714740. Its totient is φ = 1766326896.

The previous prime is 1913520793. The next prime is 1913520821. The reversal of 1913520817 is 7180253191.

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

It can be written as a sum of positive squares in 2 ways, for example, as 91853056 + 1821667761 = 9584^2 + 42681^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1913520817 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1913520877) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 73596942 + ... + 73596967.

It is an arithmetic number, because the mean of its divisors is an integer number (515178685).

Almost surely, 2^1913520817 is an apocalyptic number.

It is an amenable number.

1913520817 is a deficient number, since it is larger than the sum of its proper divisors (147193923).

1913520817 is a wasteful number, since it uses less digits than its factorization.

1913520817 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 147193922.

The product of its (nonzero) digits is 15120, while the sum is 37.

The square root of 1913520817 is about 43743.8088990888. The cubic root of 1913520817 is about 1241.4933484514.

The spelling of 1913520817 in words is "one billion, nine hundred thirteen million, five hundred twenty thousand, eight hundred seventeen".