1977604121 has 2 divisors, whose sum is σ = 1977604122. Its totient is φ = 1977604120.

The previous prime is 1977604117. The next prime is 1977604129. The reversal of 1977604121 is 1214067791.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1871514121 + 106090000 = 43261^2 + 10300^2 .

It is a cyclic number.

It is not a de Polignac number, because 1977604121 - 2² = 1977604117 is a prime.

It is not a weakly prime, because it can be changed into another prime (1977604129) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 988802060 + 988802061.

It is an arithmetic number, because the mean of its divisors is an integer number (988802061).

Almost surely, 2^1977604121 is an apocalyptic number.

It is an amenable number.

1977604121 is a deficient number, since it is larger than the sum of its proper divisors (1).

1977604121 is an equidigital number, since it uses as much as digits as its factorization.

1977604121 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 21168, while the sum is 38.

The square root of 1977604121 is about 44470.2610853591. The cubic root of 1977604121 is about 1255.2005459318.

The spelling of 1977604121 in words is "one billion, nine hundred seventy-seven million, six hundred four thousand, one hundred twenty-one".