81137782 has 8 divisors (see below), whose sum is σ = 132770952. Its totient is φ = 36880800.

The previous prime is 81137761. The next prime is 81137789. The reversal of 81137782 is 28773118.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81137789) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1844019 + ... + 1844062.

It is an arithmetic number, because the mean of its divisors is an integer number (16596369).

Almost surely, 2^81137782 is an apocalyptic number.

81137782 is a deficient number, since it is larger than the sum of its proper divisors (51633170).

81137782 is a wasteful number, since it uses less digits than its factorization.

81137782 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3688094.

The product of its digits is 18816, while the sum is 37.

The square root of 81137782 is about 9007.6513031977. The cubic root of 81137782 is about 432.9200605538.

The spelling of 81137782 in words is "eighty-one million, one hundred thirty-seven thousand, seven hundred eighty-two".