7161513721 has 16 divisors (see below), whose sum is σ = 7892467200. Its totient is φ = 6467827968.

The previous prime is 7161513679. The next prime is 7161513727. The reversal of 7161513721 is 1273151617.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 7161513721 - 2²³ = 7153125113 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (7161513727) 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, 35800 + ... + 124918.

It is an arithmetic number, because the mean of its divisors is an integer number (493279200).

Almost surely, 2^7161513721 is an apocalyptic number.

It is an amenable number.

7161513721 is a deficient number, since it is larger than the sum of its proper divisors (730953479).

7161513721 is a wasteful number, since it uses less digits than its factorization.

7161513721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 89328.

The product of its digits is 8820, while the sum is 34.

The square root of 7161513721 is about 84625.7272996812. The cubic root of 7161513721 is about 1927.5320563965.

The spelling of 7161513721 in words is "seven billion, one hundred sixty-one million, five hundred thirteen thousand, seven hundred twenty-one".