77849820 has 36 divisors (see below), whose sum is σ = 236145000. Its totient is φ = 20759904.

The previous prime is 77849809. The next prime is 77849843. The reversal of 77849820 is 2894877.

It is a tau number, because it is divible by the number of its divisors (36).

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 216070 + ... + 216429.

Almost surely, 2^77849820 is an apocalyptic number.

It is an amenable number.

77849820 is an abundant number, since it is smaller than the sum of its proper divisors (158295180).

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

77849820 is a wasteful number, since it uses less digits than its factorization.

77849820 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 432514 (or 432509 counting only the distinct ones).

The product of its (nonzero) digits is 225792, while the sum is 45.

The square root of 77849820 is about 8823.2545015997. The cubic root of 77849820 is about 426.9914749471.

The spelling of 77849820 in words is "seventy-seven million, eight hundred forty-nine thousand, eight hundred twenty".