77828491 has 8 divisors (see below), whose sum is σ = 84092624. Its totient is φ = 71604000.

The previous prime is 77828461. The next prime is 77828549. The reversal of 77828491 is 19482877.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 77828491 - 2²¹ = 75731339 is a prime.

It is a super-2 number, since 2×77828491² = 12114548022674162, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (77828441) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5760 + ... + 13741.

It is an arithmetic number, because the mean of its divisors is an integer number (10511578).

Almost surely, 2^77828491 is an apocalyptic number.

77828491 is a deficient number, since it is larger than the sum of its proper divisors (6264133).

77828491 is a wasteful number, since it uses less digits than its factorization.

77828491 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19821.

The product of its digits is 225792, while the sum is 46.

The square root of 77828491 is about 8822.0457378093. The cubic root of 77828491 is about 426.9524762142.

The spelling of 77828491 in words is "seventy-seven million, eight hundred twenty-eight thousand, four hundred ninety-one".