78280225 has 6 divisors (see below), whose sum is σ = 97067510. Its totient is φ = 62624160.

The previous prime is 78280211. The next prime is 78280259. The reversal of 78280225 is 52208287.

It can be written as a sum of positive squares in 3 ways, for example, as 10816 + 78269409 = 104^2 + 8847^2 .

It is not a de Polignac number, because 78280225 - 2²¹ = 76183073 is a prime.

It is a super-2 number, since 2×78280225² = 12255587252101250, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1565580 + ... + 1565629.

Almost surely, 2^78280225 is an apocalyptic number.

It is an amenable number.

78280225 is a deficient number, since it is larger than the sum of its proper divisors (18787285).

78280225 is a wasteful number, since it uses less digits than its factorization.

78280225 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3131219 (or 3131214 counting only the distinct ones).

The product of its (nonzero) digits is 17920, while the sum is 34.

The square root of 78280225 is about 8847.6112595434. The cubic root of 78280225 is about 427.7769257806.

The spelling of 78280225 in words is "seventy-eight million, two hundred eighty thousand, two hundred twenty-five".