771728400 has 135 divisors (see below), whose sum is σ = 2683908669. Its totient is φ = 205349760.

The previous prime is 771728383. The next prime is 771728401. The reversal of 771728400 is 4827177.

The square root of 771728400 is 27780.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 277822224 + 493906176 = 16668^2 + 22224^2 .

It is a Harshad number since it is a multiple of its sum of digits (36).

It is not an unprimeable number, because it can be changed into a prime (771728401) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 1666569 + ... + 1667031.

Almost surely, 2^771728400 is an apocalyptic number.

771728400 is the 27780-th square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 771728400

771728400 is an abundant number, since it is smaller than the sum of its proper divisors (1912180269).

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

771728400 is a wasteful number, since it uses less digits than its factorization.

771728400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 950 (or 473 counting only the distinct ones).

The product of its (nonzero) digits is 21952, while the sum is 36.

The cubic root of 771728400 is about 917.2509303704.

Multiplying 771728400 by its sum of digits (36), we get a square (27782222400 = 166680²).

771728400 divided by its sum of digits (36) gives a square (21436900 = 4630²).

The spelling of 771728400 in words is "seven hundred seventy-one million, seven hundred twenty-eight thousand, four hundred".