7273561666 has 24 divisors (see below), whose sum is σ = 12704085900. Its totient is φ = 3114179712.

The previous prime is 7273561637. The next prime is 7273561693. The reversal of 7273561666 is 6661653727.

It can be written as a sum of positive squares in 2 ways, for example, as 4445555625 + 2828006041 = 66675^2 + 53179^2 .

It is a Harshad number since it is a multiple of its sum of digits (49).

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 65310 + ... + 137158.

Almost surely, 2^7273561666 is an apocalyptic number.

7273561666 is a deficient number, since it is larger than the sum of its proper divisors (5430524234).

7273561666 is a wasteful number, since it uses less digits than its factorization.

7273561666 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 72898 (or 72891 counting only the distinct ones).

The product of its digits is 1905120, while the sum is 49.

The square root of 7273561666 is about 85285.1784661321. The cubic root of 7273561666 is about 1937.5327037477.

The spelling of 7273561666 in words is "seven billion, two hundred seventy-three million, five hundred sixty-one thousand, six hundred sixty-six".