81156634 has 8 divisors (see below), whose sum is σ = 131099220. Its totient is φ = 37456896.

The previous prime is 81156601. The next prime is 81156637. The reversal of 81156634 is 43665118.

81156634 = T₃₅₂₇ + T₃₅₂₈ + ... + T₃₅₃₉.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 80730225 + 426409 = 8985^2 + 653^2 .

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

It is a self number, because there is not a number n which added to its sum of digits gives 81156634.

It is not an unprimeable number, because it can be changed into a prime (81156637) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1560679 + ... + 1560730.

Almost surely, 2^81156634 is an apocalyptic number.

81156634 is a deficient number, since it is larger than the sum of its proper divisors (49942586).

81156634 is a wasteful number, since it uses less digits than its factorization.

81156634 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3121424.

The product of its digits is 17280, while the sum is 34.

The square root of 81156634 is about 9008.6976861253. The cubic root of 81156634 is about 432.9535869693.

The spelling of 81156634 in words is "eighty-one million, one hundred fifty-six thousand, six hundred thirty-four".