78291225 has 24 divisors (see below), whose sum is σ = 143825120. Its totient is φ = 41754960.

The previous prime is 78291209. The next prime is 78291247. The reversal of 78291225 is 52219287.

It is not a de Polignac number, because 78291225 - 2⁴ = 78291209 is a prime.

It is a super-2 number, since 2×78291225² = 12259031824001250, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 78291225.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 57319 + ... + 58668.

Almost surely, 2^78291225 is an apocalyptic number.

78291225 is a gapful number since it is divisible by the number (75) formed by its first and last digit.

It is an amenable number.

78291225 is a deficient number, since it is larger than the sum of its proper divisors (65533895).

78291225 is a wasteful number, since it uses less digits than its factorization.

78291225 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 116006 (or 115995 counting only the distinct ones).

The product of its digits is 20160, while the sum is 36.

The square root of 78291225 is about 8848.2328744219. The cubic root of 78291225 is about 427.7969620276.

The spelling of 78291225 in words is "seventy-eight million, two hundred ninety-one thousand, two hundred twenty-five".