78412889 has 8 divisors (see below), whose sum is σ = 79158600. Its totient is φ = 77670400.

The previous prime is 78412861. The next prime is 78412931. The reversal of 78412889 is 98821487.

It can be written as a sum of positive squares in 4 ways, for example, as 6451600 + 71961289 = 2540^2 + 8483^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 78412889 - 2¹² = 78408793 is a prime.

It is a super-2 number, since 2×78412889² = 12297162322652642, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (78412849) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 95099 + ... + 95919.

It is an arithmetic number, because the mean of its divisors is an integer number (9894825).

Almost surely, 2^78412889 is an apocalyptic number.

It is an amenable number.

78412889 is a deficient number, since it is larger than the sum of its proper divisors (745711).

78412889 is a wasteful number, since it uses less digits than its factorization.

78412889 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1611.

The product of its digits is 258048, while the sum is 47.

The square root of 78412889 is about 8855.1052506450. The cubic root of 78412889 is about 428.0184451392.

The spelling of 78412889 in words is "seventy-eight million, four hundred twelve thousand, eight hundred eighty-nine".