1972217979 has 6 divisors (see below), whose sum is σ = 2848759316. Its totient is φ = 1314811980.

The previous prime is 1972217977. The next prime is 1972217983. The reversal of 1972217979 is 9797122791.

It is not a de Polignac number, because 1972217979 - 2¹ = 1972217977 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1972217971) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 109567657 + ... + 109567674.

Almost surely, 2^1972217979 is an apocalyptic number.

1972217979 is a deficient number, since it is larger than the sum of its proper divisors (876541337).

1972217979 is a wasteful number, since it uses less digits than its factorization.

1972217979 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 219135337 (or 219135334 counting only the distinct ones).

The product of its digits is 1000188, while the sum is 54.

The square root of 1972217979 is about 44409.6608746340. The cubic root of 1972217979 is about 1254.0599679052.

The spelling of 1972217979 in words is "one billion, nine hundred seventy-two million, two hundred seventeen thousand, nine hundred seventy-nine".