77947842 has 96 divisors (see below), whose sum is σ = 193560192. Its totient is φ = 20487168.

The previous prime is 77947829. The next prime is 77947871. The reversal of 77947842 is 24874977.

It is a junction number, because it is equal to n+sod(n) for n = 77947791 and 77947800.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 803538 + ... + 803634.

It is an arithmetic number, because the mean of its divisors is an integer number (2016252).

Almost surely, 2^77947842 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 77947842, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (96780096).

77947842 is an abundant number, since it is smaller than the sum of its proper divisors (115612350).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

77947842 is a wasteful number, since it uses less digits than its factorization.

77947842 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 200 (or 181 counting only the distinct ones).

The product of its digits is 790272, while the sum is 48.

The square root of 77947842 is about 8828.8075072458. The cubic root of 77947842 is about 427.1706104675.

The spelling of 77947842 in words is "seventy-seven million, nine hundred forty-seven thousand, eight hundred forty-two".