78513998091 has 16 divisors (see below), whose sum is σ = 110310791040. Its totient is φ = 49535720640.

The previous prime is 78513998071. The next prime is 78513998111. The reversal of 78513998091 is 19089931587.

It is an interprime number because it is at equal distance from previous prime (78513998071) and next prime (78513998111).

It is not a de Polignac number, because 78513998091 - 2⁶ = 78513998027 is a prime.

It is not an unprimeable number, because it can be changed into a prime (78513998021) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 668365 + ... + 777006.

It is an arithmetic number, because the mean of its divisors is an integer number (6894424440).

Almost surely, 2^78513998091 is an apocalyptic number.

78513998091 is a deficient number, since it is larger than the sum of its proper divisors (31796792949).

78513998091 is a wasteful number, since it uses less digits than its factorization.

78513998091 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1446346.

The product of its (nonzero) digits is 4898880, while the sum is 60.

The spelling of 78513998091 in words is "seventy-eight billion, five hundred thirteen million, nine hundred ninety-eight thousand, ninety-one".