78890129 has 4 divisors (see below), whose sum is σ = 80378676. Its totient is φ = 77401584.

The previous prime is 78890113. The next prime is 78890131. The reversal of 78890129 is 92109887.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 92109887 = 29 ⋅3176203.

It can be written as a sum of positive squares in 2 ways, for example, as 59985025 + 18905104 = 7745^2 + 4348^2 .

It is a cyclic number.

It is not a de Polignac number, because 78890129 - 2⁴ = 78890113 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 78890129.

It is not an unprimeable number, because it can be changed into a prime (78898129) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 744194 + ... + 744299.

It is an arithmetic number, because the mean of its divisors is an integer number (20094669).

Almost surely, 2^78890129 is an apocalyptic number.

It is an amenable number.

78890129 is a deficient number, since it is larger than the sum of its proper divisors (1488547).

78890129 is a wasteful number, since it uses less digits than its factorization.

78890129 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1488546.

The product of its (nonzero) digits is 72576, while the sum is 44.

The square root of 78890129 is about 8882.0115401862. The cubic root of 78890129 is about 428.8850310350.

The spelling of 78890129 in words is "seventy-eight million, eight hundred ninety thousand, one hundred twenty-nine".