1977557 has 2 divisors, whose sum is σ = 1977558. Its totient is φ = 1977556.

The previous prime is 1977551. The next prime is 1977571. The reversal of 1977557 is 7557791.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1653796 + 323761 = 1286^2 + 569^2 .

It is a cyclic number.

It is not a de Polignac number, because 1977557 - 2⁴ = 1977541 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1977551) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 988778 + 988779.

It is an arithmetic number, because the mean of its divisors is an integer number (988779).

2^1977557 is an apocalyptic number.

It is an amenable number.

1977557 is a deficient number, since it is larger than the sum of its proper divisors (1).

1977557 is an equidigital number, since it uses as much as digits as its factorization.

1977557 is an evil number, because the sum of its binary digits is even.

The product of its digits is 77175, while the sum is 41.

The square root of 1977557 is about 1406.2563777633. The cubic root of 1977557 is about 125.5190576499.

The spelling of 1977557 in words is "one million, nine hundred seventy-seven thousand, five hundred fifty-seven".