81250981 has 8 divisors (see below), whose sum is σ = 93245504. Its totient is φ = 69353280.

The previous prime is 81250979. The next prime is 81250991. The reversal of 81250981 is 18905218.

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

It is a cyclic number.

It is not a de Polignac number, because 81250981 - 2¹ = 81250979 is a prime.

It is a super-2 number, since 2×81250981² = 13203443826924722, which contains 22 as substring.

It is an alternating number because its digits alternate between even and odd.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81250931) 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, 22395 + ... + 25768.

It is an arithmetic number, because the mean of its divisors is an integer number (11655688).

Almost surely, 2^81250981 is an apocalyptic number.

It is an amenable number.

81250981 is a deficient number, since it is larger than the sum of its proper divisors (11994523).

81250981 is a wasteful number, since it uses less digits than its factorization.

81250981 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 48411.

The product of its (nonzero) digits is 5760, while the sum is 34.

The square root of 81250981 is about 9013.9326045850. The cubic root of 81250981 is about 433.1212958031.

The spelling of 81250981 in words is "eighty-one million, two hundred fifty thousand, nine hundred eighty-one".