78467891 has 16 divisors (see below), whose sum is σ = 85155840. Its totient is φ = 72060480.

The previous prime is 78467867. The next prime is 78467897. The reversal of 78467891 is 19876487.

78467891 = T₄₃₉ + T₄₄₀ + ... + T₈₂₁.

It is a cyclic number.

It is not a de Polignac number, because 78467891 - 2²⁶ = 11359027 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (78467897) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 204686 + ... + 205068.

It is an arithmetic number, because the mean of its divisors is an integer number (5322240).

Almost surely, 2^78467891 is an apocalyptic number.

78467891 is a deficient number, since it is larger than the sum of its proper divisors (6687949).

78467891 is a wasteful number, since it uses less digits than its factorization.

78467891 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 706.

The product of its digits is 677376, while the sum is 50.

The square root of 78467891 is about 8858.2103723043. The cubic root of 78467891 is about 428.1184982833.

The spelling of 78467891 in words is "seventy-eight million, four hundred sixty-seven thousand, eight hundred ninety-one".