81378414 has 24 divisors (see below), whose sum is σ = 189883512. Its totient is φ = 25039440.

The previous prime is 81378413. The next prime is 81378421. The reversal of 81378414 is 41487318.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81378413) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 173652 + ... + 174119.

It is an arithmetic number, because the mean of its divisors is an integer number (7911813).

Almost surely, 2^81378414 is an apocalyptic number.

81378414 is an abundant number, since it is smaller than the sum of its proper divisors (108505098).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

81378414 is a wasteful number, since it uses less digits than its factorization.

81378414 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 347792 (or 347789 counting only the distinct ones).

The product of its digits is 21504, while the sum is 36.

The square root of 81378414 is about 9020.9985034917. The cubic root of 81378414 is about 433.3476114953.

The spelling of 81378414 in words is "eighty-one million, three hundred seventy-eight thousand, four hundred fourteen".