977821663 has 12 divisors (see below), whose sum is σ = 1210086768. Its totient is φ = 773660160.

The previous prime is 977821661. The next prime is 977821667. The reversal of 977821663 is 366128779.

It is a happy number.

It is not a de Polignac number, because 977821663 - 2¹ = 977821661 is a prime.

It is a super-2 number, since 2×977821663² = 1912270409264171138, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (977821661) 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 in 11 ways as a sum of consecutive naturals, for example, 412098 + ... + 414463.

It is an arithmetic number, because the mean of its divisors is an integer number (100840564).

Almost surely, 2^977821663 is an apocalyptic number.

977821663 is a deficient number, since it is larger than the sum of its proper divisors (232265105).

977821663 is a wasteful number, since it uses less digits than its factorization.

977821663 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 826594 (or 826581 counting only the distinct ones).

The product of its digits is 762048, while the sum is 49.

The square root of 977821663 is about 31270.1401180103. The cubic root of 977821663 is about 992.5518842992.

The spelling of 977821663 in words is "nine hundred seventy-seven million, eight hundred twenty-one thousand, six hundred sixty-three".