77521998887 has 2 divisors, whose sum is σ = 77521998888. Its totient is φ = 77521998886.

The previous prime is 77521998859. The next prime is 77521998899. The reversal of 77521998887 is 78889912577.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 77521998887 - 2⁶ = 77521998823 is a prime.

It is a super-2 number, since 2×77521998887² (a number of 23 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 77521998887.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (77521998187) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 38760999443 + 38760999444.

It is an arithmetic number, because the mean of its divisors is an integer number (38760999444).

Almost surely, 2^77521998887 is an apocalyptic number.

77521998887 is a deficient number, since it is larger than the sum of its proper divisors (1).

77521998887 is an equidigital number, since it uses as much as digits as its factorization.

77521998887 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 142248960, while the sum is 71.

The spelling of 77521998887 in words is "seventy-seven billion, five hundred twenty-one million, nine hundred ninety-eight thousand, eight hundred eighty-seven".