977681 has 2 divisors, whose sum is σ = 977682. Its totient is φ = 977680.

The previous prime is 977671. The next prime is 977693. The reversal of 977681 is 186779.

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., 707281 + 270400 = 841^2 + 520^2 .

It is a cyclic number.

It is not a de Polignac number, because 977681 - 2¹⁸ = 715537 is a prime.

It is a super-2 number, since 2×977681² = 1911720275522, which contains 22 as substring.

It is a nialpdrome in base 16.

It is not a weakly prime, because it can be changed into another prime (977611) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 488840 + 488841.

It is an arithmetic number, because the mean of its divisors is an integer number (488841).

2⁹⁷⁷⁶⁸¹ is an apocalyptic number.

It is an amenable number.

977681 is a deficient number, since it is larger than the sum of its proper divisors (1).

977681 is an equidigital number, since it uses as much as digits as its factorization.

977681 is an odious number, because the sum of its binary digits is odd.

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

The square root of 977681 is about 988.7775280618. Note that the first 3 decimals coincide. The cubic root of 977681 is about 99.2504288019.

The spelling of 977681 in words is "nine hundred seventy-seven thousand, six hundred eighty-one".