7645367721 has 32 divisors (see below), whose sum is σ = 10905373440. Its totient is φ = 4747618304.

The previous prime is 7645367699. The next prime is 7645367729. The reversal of 7645367721 is 1277635467.

It is a cyclic number.

It is not a de Polignac number, because 7645367721 - 2⁹ = 7645367209 is a prime.

It is not an unprimeable number, because it can be changed into a prime (7645367729) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 2053900 + ... + 2057618.

It is an arithmetic number, because the mean of its divisors is an integer number (340792920).

Almost surely, 2^7645367721 is an apocalyptic number.

It is an amenable number.

7645367721 is a deficient number, since it is larger than the sum of its proper divisors (3260005719).

7645367721 is a wasteful number, since it uses less digits than its factorization.

7645367721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4145.

The product of its digits is 1481760, while the sum is 48.

The square root of 7645367721 is about 87437.7934362481. The cubic root of 7645367721 is about 1969.9995465827. Note that the first 3 decimals are identical.

The spelling of 7645367721 in words is "seven billion, six hundred forty-five million, three hundred sixty-seven thousand, seven hundred twenty-one".