81156794 has 16 divisors (see below), whose sum is σ = 124989480. Its totient is φ = 39498240.

The previous prime is 81156773. The next prime is 81156821. The reversal of 81156794 is 49765118.

It can be written as a sum of positive squares in 4 ways, for example, as 55279225 + 25877569 = 7435^2 + 5087^2 .

It is a Harshad number since it is a multiple of its sum of digits (41).

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 47792 + ... + 49460.

Almost surely, 2^81156794 is an apocalyptic number.

81156794 is a deficient number, since it is larger than the sum of its proper divisors (43832686).

81156794 is a wasteful number, since it uses less digits than its factorization.

81156794 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2305.

The product of its digits is 60480, while the sum is 41.

The square root of 81156794 is about 9008.7065664278. The cubic root of 81156794 is about 432.9538714912.

The spelling of 81156794 in words is "eighty-one million, one hundred fifty-six thousand, seven hundred ninety-four".