1972738945 has 4 divisors (see below), whose sum is σ = 2367286740. Its totient is φ = 1578191152.

The previous prime is 1972738921. The next prime is 1972738961. The reversal of 1972738945 is 5498372791.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 5498372791 = 4357 ⋅1261963.

It can be written as a sum of positive squares in 2 ways, for example, as 959017024 + 1013721921 = 30968^2 + 31839^2 .

It is a cyclic number.

It is not a de Polignac number, because 1972738945 - 2⁵ = 1972738913 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 197273890 + ... + 197273899.

It is an arithmetic number, because the mean of its divisors is an integer number (591821685).

Almost surely, 2^1972738945 is an apocalyptic number.

It is an amenable number.

1972738945 is a deficient number, since it is larger than the sum of its proper divisors (394547795).

1972738945 is an equidigital number, since it uses as much as digits as its factorization.

1972738945 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 394547794.

The product of its digits is 3810240, while the sum is 55.

The square root of 1972738945 is about 44415.5259453268. The cubic root of 1972738945 is about 1254.1703791435.

The spelling of 1972738945 in words is "one billion, nine hundred seventy-two million, seven hundred thirty-eight thousand, nine hundred forty-five".