7122645561 has 4 divisors (see below), whose sum is σ = 9496860752. Its totient is φ = 4748430372.

The previous prime is 7122645557. The next prime is 7122645587. The reversal of 7122645561 is 1655462217.

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 not a de Polignac number, because 7122645561 - 2² = 7122645557 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (7122647561) 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, 1187107591 + ... + 1187107596.

It is an arithmetic number, because the mean of its divisors is an integer number (2374215188).

Almost surely, 2^7122645561 is an apocalyptic number.

It is an amenable number.

7122645561 is a deficient number, since it is larger than the sum of its proper divisors (2374215191).

7122645561 is a wasteful number, since it uses less digits than its factorization.

7122645561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2374215190.

The product of its digits is 100800, while the sum is 39.

The square root of 7122645561 is about 84395.7674353400. The cubic root of 7122645561 is about 1924.0385876406.

The spelling of 7122645561 in words is "seven billion, one hundred twenty-two million, six hundred forty-five thousand, five hundred sixty-one".