7656660401 has 4 divisors (see below), whose sum is σ = 8245634292. Its totient is φ = 7067686512.

The previous prime is 7656660353. The next prime is 7656660437. The reversal of 7656660401 is 1040666567.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1040666567 = 1489 ⋅698903.

It can be written as a sum of positive squares in 2 ways, for example, as 556912801 + 7099747600 = 23599^2 + 84260^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-7656660401 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (7656660701) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 294486926 + ... + 294486951.

It is an arithmetic number, because the mean of its divisors is an integer number (2061408573).

Almost surely, 2^7656660401 is an apocalyptic number.

It is an amenable number.

7656660401 is a deficient number, since it is larger than the sum of its proper divisors (588973891).

7656660401 is a wasteful number, since it uses less digits than its factorization.

7656660401 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 588973890.

The product of its (nonzero) digits is 181440, while the sum is 41.

The square root of 7656660401 is about 87502.3451171453. The cubic root of 7656660401 is about 1970.9690063952.

The spelling of 7656660401 in words is "seven billion, six hundred fifty-six million, six hundred sixty thousand, four hundred one".