77423640 has 128 divisors (see below), whose sum is σ = 269982720. Its totient is φ = 17395200.

The previous prime is 77423639. The next prime is 77423663. The reversal of 77423640 is 4632477.

It is a congruent number.

It is an unprimeable number.

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 31 ways as a sum of consecutive naturals, for example, 50485 + ... + 51995.

It is an arithmetic number, because the mean of its divisors is an integer number (2109240).

Almost surely, 2^77423640 is an apocalyptic number.

77423640 is a gapful number since it is divisible by the number (70) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 77423640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (134991360).

77423640 is an abundant number, since it is smaller than the sum of its proper divisors (192559080).

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

77423640 is a wasteful number, since it uses less digits than its factorization.

77423640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1593 (or 1589 counting only the distinct ones).

The product of its (nonzero) digits is 28224, while the sum is 33.

The square root of 77423640 is about 8799.0704054462. The cubic root of 77423640 is about 426.2108766619.

The spelling of 77423640 in words is "seventy-seven million, four hundred twenty-three thousand, six hundred forty".