1977316217 has 2 divisors, whose sum is σ = 1977316218. Its totient is φ = 1977316216.

The previous prime is 1977316199. The next prime is 1977316259. The reversal of 1977316217 is 7126137791.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1525371136 + 451945081 = 39056^2 + 21259^2 .

It is a cyclic number.

It is not a de Polignac number, because 1977316217 - 2⁶ = 1977316153 is a prime.

It is a super-2 number, since 2×1977316217² = 7819558844022382178, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (1977316267) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 988658108 + 988658109.

It is an arithmetic number, because the mean of its divisors is an integer number (988658109).

Almost surely, 2^1977316217 is an apocalyptic number.

It is an amenable number.

1977316217 is a deficient number, since it is larger than the sum of its proper divisors (1).

1977316217 is an equidigital number, since it uses as much as digits as its factorization.

1977316217 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 111132, while the sum is 44.

The square root of 1977316217 is about 44467.0239278502. The cubic root of 1977316217 is about 1255.1396313479.

The spelling of 1977316217 in words is "one billion, nine hundred seventy-seven million, three hundred sixteen thousand, two hundred seventeen".