78387401 has 4 divisors (see below), whose sum is σ = 78566400. Its totient is φ = 78208404.

The previous prime is 78387389. The next prime is 78387457. The reversal of 78387401 is 10478387.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 78387401 - 2²⁶ = 11278537 is a prime.

It is a super-2 number, since 2×78387401² = 12289169271069602, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (78387481) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 88841 + ... + 89718.

It is an arithmetic number, because the mean of its divisors is an integer number (19641600).

Almost surely, 2^78387401 is an apocalyptic number.

It is an amenable number.

78387401 is a deficient number, since it is larger than the sum of its proper divisors (178999).

78387401 is a wasteful number, since it uses less digits than its factorization.

78387401 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 178998.

The product of its (nonzero) digits is 37632, while the sum is 38.

The square root of 78387401 is about 8853.6659638819. The cubic root of 78387401 is about 427.9720645144.

The spelling of 78387401 in words is "seventy-eight million, three hundred eighty-seven thousand, four hundred one".