77520825 has 36 divisors (see below), whose sum is σ = 140123100. Its totient is φ = 40965120.

The previous prime is 77520811. The next prime is 77520847. The reversal of 77520825 is 52802577.

It can be written as a sum of positive squares in 6 ways, for example, as 31674384 + 45846441 = 5628^2 + 6771^2 .

It is not a de Polignac number, because 77520825 - 2¹⁸ = 77258681 is a prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 77520825.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 23901 + ... + 26949.

Almost surely, 2^77520825 is an apocalyptic number.

77520825 is a gapful number since it is divisible by the number (75) formed by its first and last digit.

It is an amenable number.

77520825 is a deficient number, since it is larger than the sum of its proper divisors (62602275).

77520825 is a wasteful number, since it uses less digits than its factorization.

77520825 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3178 (or 3170 counting only the distinct ones).

The product of its (nonzero) digits is 39200, while the sum is 36.

The square root of 77520825 is about 8804.5911319039. The cubic root of 77520825 is about 426.3891339527.

The spelling of 77520825 in words is "seventy-seven million, five hundred twenty thousand, eight hundred twenty-five".