81277100 has 36 divisors (see below), whose sum is σ = 180134304. Its totient is φ = 31817280.

The previous prime is 81277099. The next prime is 81277103. The reversal of 81277100 is 177218.

It is a self number, because there is not a number n which added to its sum of digits gives 81277100.

It is not an unprimeable number, because it can be changed into a prime (81277103) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 3947 + ... + 13346.

Almost surely, 2^81277100 is an apocalyptic number.

It is an amenable number.

81277100 is an abundant number, since it is smaller than the sum of its proper divisors (98857204).

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

81277100 is a wasteful number, since it uses less digits than its factorization.

81277100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17354 (or 17347 counting only the distinct ones).

The product of its (nonzero) digits is 784, while the sum is 26.

The square root of 81277100 is about 9015.3813008658. The cubic root of 81277100 is about 433.1677013275.

The spelling of 81277100 in words is "eighty-one million, two hundred seventy-seven thousand, one hundred".