7406780661 has 18 divisors (see below), whose sum is σ = 12445407702. Its totient is φ = 4232445840.

The previous prime is 7406780651. The next prime is 7406780683. The reversal of 7406780661 is 1660876047.

It can be written as a sum of positive squares in only one way, i.e., 7038371025 + 368409636 = 83895^2 + 19194^2 .

It is not a de Polignac number, because 7406780661 - 2⁵ = 7406780629 is a prime.

It is a hoax number, since the sum of its digits (45) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (7406780651) by changing a digit.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 8397270 + ... + 8398151.

It is an arithmetic number, because the mean of its divisors is an integer number (691411539).

Almost surely, 2^7406780661 is an apocalyptic number.

It is an amenable number.

7406780661 is a deficient number, since it is larger than the sum of its proper divisors (5038627041).

7406780661 is a wasteful number, since it uses less digits than its factorization.

7406780661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16795441 (or 16795431 counting only the distinct ones).

The product of its (nonzero) digits is 338688, while the sum is 45.

The square root of 7406780661 is about 86062.6554377681. The cubic root of 7406780661 is about 1949.2901787295.

The spelling of 7406780661 in words is "seven billion, four hundred six million, seven hundred eighty thousand, six hundred sixty-one".