91967378 has 4 divisors (see below), whose sum is σ = 137951070. Its totient is φ = 45983688.

The previous prime is 91967377. The next prime is 91967383. The reversal of 91967378 is 87376919.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 87376919 = 7 ⋅12482417.

It can be written as a sum of positive squares in only one way, i.e., 72369049 + 19598329 = 8507^2 + 4427^2 .

It is a super-3 number, since 3×91967378³ (a number of 25 digits) contains 333 as substring.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (91967377) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 22991843 + ... + 22991846.

Almost surely, 2^91967378 is an apocalyptic number.

91967378 is a deficient number, since it is larger than the sum of its proper divisors (45983692).

91967378 is a wasteful number, since it uses less digits than its factorization.

91967378 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 45983691.

The product of its digits is 571536, while the sum is 50.

The square root of 91967378 is about 9589.9623565476. The cubic root of 91967378 is about 451.3823794974.

The spelling of 91967378 in words is "ninety-one million, nine hundred sixty-seven thousand, three hundred seventy-eight".