1361972779 has 4 divisors (see below), whose sum is σ = 1375457760. Its totient is φ = 1348487800.

The previous prime is 1361972707. The next prime is 1361972797. The reversal of 1361972779 is 9772791631.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 1361972779 - 2²⁵ = 1328418347 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1361976779) 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, 6742339 + ... + 6742540.

It is an arithmetic number, because the mean of its divisors is an integer number (343864440).

Almost surely, 2^1361972779 is an apocalyptic number.

1361972779 is a deficient number, since it is larger than the sum of its proper divisors (13484981).

1361972779 is a wasteful number, since it uses less digits than its factorization.

1361972779 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13484980.

The product of its digits is 1000188, while the sum is 52.

The square root of 1361972779 is about 36904.9153772231. The cubic root of 1361972779 is about 1108.4671043668.

The spelling of 1361972779 in words is "one billion, three hundred sixty-one million, nine hundred seventy-two thousand, seven hundred seventy-nine".