7403561661 has 4 divisors (see below), whose sum is σ = 9871415552. Its totient is φ = 4935707772.

The previous prime is 7403561653. The next prime is 7403561663. The reversal of 7403561661 is 1661653047.

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, and also an emirpimes, since its reverse is a distinct semiprime: 1661653047 = 3 ⋅553884349.

It is not a de Polignac number, because 7403561661 - 2³ = 7403561653 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (7403561663) 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, 1233926941 + ... + 1233926946.

It is an arithmetic number, because the mean of its divisors is an integer number (2467853888).

Almost surely, 2^7403561661 is an apocalyptic number.

It is an amenable number.

7403561661 is a deficient number, since it is larger than the sum of its proper divisors (2467853891).

7403561661 is a wasteful number, since it uses less digits than its factorization.

7403561661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2467853890.

The product of its (nonzero) digits is 90720, while the sum is 39.

The square root of 7403561661 is about 86043.9519141235. The cubic root of 7403561661 is about 1949.0077494889.

The spelling of 7403561661 in words is "seven billion, four hundred three million, five hundred sixty-one thousand, six hundred sixty-one".