77985225 has 18 divisors (see below), whose sum is σ = 139680606. Its totient is φ = 41592000.

The previous prime is 77985209. The next prime is 77985227. The reversal of 77985225 is 52258977.

It is a happy number.

It can be written as a sum of positive squares in 3 ways, for example, as 16064064 + 61921161 = 4008^2 + 7869^2 .

It is not a de Polignac number, because 77985225 - 2⁴ = 77985209 is a prime.

It is a super-3 number, since 3×77985225³ (a number of 25 digits) contains 333 as substring.

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

It is not an unprimeable number, because it can be changed into a prime (77985227) by changing a digit.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 173076 + ... + 173525.

Almost surely, 2^77985225 is an apocalyptic number.

77985225 is a gapful number since it is divisible by the number (75) formed by its first and last digit.

It is an amenable number.

77985225 is a deficient number, since it is larger than the sum of its proper divisors (61695381).

77985225 is a wasteful number, since it uses less digits than its factorization.

77985225 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 346617 (or 346609 counting only the distinct ones).

The product of its digits is 352800, while the sum is 45.

The square root of 77985225 is about 8830.9243570535. The cubic root of 77985225 is about 427.2388884611.

It can be divided in two parts, 77985 and 225, that added together give a triangular number (78210 = T₃₉₅).

The spelling of 77985225 in words is "seventy-seven million, nine hundred eighty-five thousand, two hundred twenty-five".