78351813 has 8 divisors (see below), whose sum is σ = 116076800. Its totient is φ = 52234524.

The previous prime is 78351811. The next prime is 78351817. The reversal of 78351813 is 31815387.

It is not a de Polignac number, because 78351813 - 2¹ = 78351811 is a prime.

It is a super-2 number, since 2×78351813² = 12278013200773938, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78351811) 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, 1450933 + ... + 1450986.

It is an arithmetic number, because the mean of its divisors is an integer number (14509600).

Almost surely, 2^78351813 is an apocalyptic number.

It is an amenable number.

78351813 is a deficient number, since it is larger than the sum of its proper divisors (37724987).

78351813 is a wasteful number, since it uses less digits than its factorization.

78351813 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2901928 (or 2901922 counting only the distinct ones).

The product of its digits is 20160, while the sum is 36.

The square root of 78351813 is about 8851.6559467706. The cubic root of 78351813 is about 427.9072880531.

The spelling of 78351813 in words is "seventy-eight million, three hundred fifty-one thousand, eight hundred thirteen".