77229840 has 80 divisors (see below), whose sum is σ = 242359488. Its totient is φ = 20341248.

The previous prime is 77229797. The next prime is 77229863. The reversal of 77229840 is 4892277.

It is a tau number, because it is divible by the number of its divisors (80).

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 17982 + ... + 21858.

Almost surely, 2^77229840 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 77229840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (121179744).

77229840 is an abundant number, since it is smaller than the sum of its proper divisors (165129648).

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

77229840 is a wasteful number, since it uses less digits than its factorization.

77229840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3976 (or 3970 counting only the distinct ones).

The product of its (nonzero) digits is 56448, while the sum is 39.

The square root of 77229840 is about 8788.0509784593. The cubic root of 77229840 is about 425.8549617561.

The spelling of 77229840 in words is "seventy-seven million, two hundred twenty-nine thousand, eight hundred forty".