78776553 has 4 divisors (see below), whose sum is σ = 105035408. Its totient is φ = 52517700.

The previous prime is 78776519. The next prime is 78776561. The reversal of 78776553 is 35567787.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 78776553 - 2¹⁸ = 78514409 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (78776573) 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 in 3 ways as a sum of consecutive naturals, for example, 13129423 + ... + 13129428.

It is an arithmetic number, because the mean of its divisors is an integer number (26258852).

Almost surely, 2^78776553 is an apocalyptic number.

It is an amenable number.

78776553 is a deficient number, since it is larger than the sum of its proper divisors (26258855).

78776553 is a wasteful number, since it uses less digits than its factorization.

78776553 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26258854.

The product of its digits is 1234800, while the sum is 48.

The square root of 78776553 is about 8875.6156406190. The cubic root of 78776553 is about 428.6791140987.

The spelling of 78776553 in words is "seventy-eight million, seven hundred seventy-six thousand, five hundred fifty-three".