1972781345 has 16 divisors (see below), whose sum is σ = 2387480400. Its totient is φ = 1564852224.

The previous prime is 1972781329. The next prime is 1972781353. The reversal of 1972781345 is 5431872791.

It can be written as a sum of positive squares in 8 ways, for example, as 59243809 + 1913537536 = 7697^2 + 43744^2 .

It is a cyclic number.

It is not a de Polignac number, because 1972781345 - 2⁴ = 1972781329 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1972781345.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 302681 + ... + 309129.

It is an arithmetic number, because the mean of its divisors is an integer number (149217525).

Almost surely, 2^1972781345 is an apocalyptic number.

It is an amenable number.

1972781345 is a deficient number, since it is larger than the sum of its proper divisors (414699055).

1972781345 is a wasteful number, since it uses less digits than its factorization.

1972781345 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6964.

The product of its digits is 423360, while the sum is 47.

The square root of 1972781345 is about 44416.0032533320. The cubic root of 1972781345 is about 1254.1793643572.

The spelling of 1972781345 in words is "one billion, nine hundred seventy-two million, seven hundred eighty-one thousand, three hundred forty-five".