82783981 has 12 divisors (see below), whose sum is σ = 99408000. Its totient is φ = 68667480.

The previous prime is 82783979. The next prime is 82784003. The reversal of 82783981 is 18938728.

It is not a de Polignac number, because 82783981 - 2¹ = 82783979 is a prime.

It is a super-2 number, since 2×82783981² = 13706375020416722, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (82783381) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 25731 + ... + 28768.

It is an arithmetic number, because the mean of its divisors is an integer number (8284000).

Almost surely, 2^82783981 is an apocalyptic number.

It is an amenable number.

82783981 is a deficient number, since it is larger than the sum of its proper divisors (16624019).

82783981 is a wasteful number, since it uses less digits than its factorization.

82783981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 54544 (or 54537 counting only the distinct ones).

The product of its digits is 193536, while the sum is 46.

The square root of 82783981 is about 9098.5702723010. The cubic root of 82783981 is about 435.8283085878.

The spelling of 82783981 in words is "eighty-two million, seven hundred eighty-three thousand, nine hundred eighty-one".