7640476721 has 4 divisors (see below), whose sum is σ = 7886943744. Its totient is φ = 7394009700.

The previous prime is 7640476709. The next prime is 7640476729. The reversal of 7640476721 is 1276740467.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-7640476721 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (7640476729) 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, 123233465 + ... + 123233526.

It is an arithmetic number, because the mean of its divisors is an integer number (1971735936).

Almost surely, 2^7640476721 is an apocalyptic number.

It is an amenable number.

7640476721 is a deficient number, since it is larger than the sum of its proper divisors (246467023).

7640476721 is a wasteful number, since it uses less digits than its factorization.

7640476721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 246467022.

The product of its (nonzero) digits is 395136, while the sum is 44.

The square root of 7640476721 is about 87409.8205066227. The cubic root of 7640476721 is about 1969.5793652157.

The spelling of 7640476721 in words is "seven billion, six hundred forty million, four hundred seventy-six thousand, seven hundred twenty-one".