977621 has 4 divisors (see below), whose sum is σ = 986700. Its totient is φ = 968544.

The previous prime is 977611. The next prime is 977629. The reversal of 977621 is 126779.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 126779 = 97 ⋅1307.

It can be written as a sum of positive squares in 2 ways, for example, as 600625 + 376996 = 775^2 + 614^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-977621 is a prime.

It is a Duffinian number.

It is a nialpdrome in base 10.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (977629) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4376 + ... + 4593.

It is an arithmetic number, because the mean of its divisors is an integer number (246675).

2⁹⁷⁷⁶²¹ is an apocalyptic number.

It is an amenable number.

977621 is a deficient number, since it is larger than the sum of its proper divisors (9079).

977621 is a wasteful number, since it uses less digits than its factorization.

977621 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9078.

The product of its digits is 5292, while the sum is 32.

The square root of 977621 is about 988.7471871009. The cubic root of 977621 is about 99.2483984370.

The spelling of 977621 in words is "nine hundred seventy-seven thousand, six hundred twenty-one".