81277120 has 56 divisors (see below), whose sum is σ = 194310000. Its totient is φ = 32381952.

The previous prime is 81277103. The next prime is 81277121. The reversal of 81277120 is 2177218.

It is not an unprimeable number, because it can be changed into a prime (81277121) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 159426 + ... + 159934.

Almost surely, 2^81277120 is an apocalyptic number.

81277120 is a gapful number since it is divisible by the number (80) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 81277120, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (97155000).

81277120 is an abundant number, since it is smaller than the sum of its proper divisors (113032880).

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

81277120 is a wasteful number, since it uses less digits than its factorization.

81277120 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1025 (or 1015 counting only the distinct ones).

The product of its (nonzero) digits is 1568, while the sum is 28.

The square root of 81277120 is about 9015.3824100811. The cubic root of 81277120 is about 433.1677368576.

The spelling of 81277120 in words is "eighty-one million, two hundred seventy-seven thousand, one hundred twenty".