75981 has 16 divisors (see below), whose sum is σ = 112640. Its totient is φ = 45360.

The previous prime is 75979. The next prime is 75983. The reversal of 75981 is 18957.

75981 = 54² + 55² + ... + 72².

75981 is an esthetic number in base 7, because in such base its adjacent digits differ by 1.

It is an interprime number because it is at equal distance from previous prime (75979) and next prime (75983).

It is not a de Polignac number, because 75981 - 2¹ = 75979 is a prime.

It is a super-2 number, since 2×75981² = 11546224722, which contains 22 as substring.

It is a Duffinian number.

75981 is an undulating number in base 7.

It is a plaindrome in base 16.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (75983) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1746 + ... + 1788.

It is an arithmetic number, because the mean of its divisors is an integer number (7040).

2⁷⁵⁹⁸¹ is an apocalyptic number.

It is an amenable number.

75981 is a deficient number, since it is larger than the sum of its proper divisors (36659).

75981 is a wasteful number, since it uses less digits than its factorization.

75981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 96.

The product of its digits is 2520, while the sum is 30.

The square root of 75981 is about 275.6465127659. The cubic root of 75981 is about 42.3547056954.

The spelling of 75981 in words is "seventy-five thousand, nine hundred eighty-one".