81406278 has 24 divisors (see below), whose sum is σ = 176551128. Its totient is φ = 27109152.

The previous prime is 81406249. The next prime is 81406291. The reversal of 81406278 is 87260418.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 28650 + ... + 31362.

It is an arithmetic number, because the mean of its divisors is an integer number (7356297).

Almost surely, 2^81406278 is an apocalyptic number.

81406278 is an abundant number, since it is smaller than the sum of its proper divisors (95144850).

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

81406278 is a wasteful number, since it uses less digits than its factorization.

81406278 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4388 (or 4385 counting only the distinct ones).

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

The square root of 81406278 is about 9022.5427679784. The cubic root of 81406278 is about 433.3970653139.

The spelling of 81406278 in words is "eighty-one million, four hundred six thousand, two hundred seventy-eight".