78181431 has 8 divisors (see below), whose sum is σ = 106008960. Its totient is φ = 51237432.

The previous prime is 78181417. The next prime is 78181463. The reversal of 78181431 is 13418187.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 78181431 - 2⁵ = 78181399 is a prime.

It is a super-2 number, since 2×78181431² = 12224672306415522, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 78181392 and 78181401.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78189431) 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, 220675 + ... + 221028.

It is an arithmetic number, because the mean of its divisors is an integer number (13251120).

Almost surely, 2^78181431 is an apocalyptic number.

78181431 is a deficient number, since it is larger than the sum of its proper divisors (27827529).

78181431 is a wasteful number, since it uses less digits than its factorization.

78181431 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 441765.

The product of its digits is 5376, while the sum is 33.

The square root of 78181431 is about 8842.0264080130. The cubic root of 78181431 is about 427.5968905929.

The spelling of 78181431 in words is "seventy-eight million, one hundred eighty-one thousand, four hundred thirty-one".