82666440 has 64 divisors (see below), whose sum is σ = 275558400. Its totient is φ = 22044096.

The previous prime is 82666421. The next prime is 82666447. The reversal of 82666440 is 4466628.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 82666395 and 82666404.

It is not an unprimeable number, because it can be changed into a prime (82666447) 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, 37192 + ... + 39351.

It is an arithmetic number, because the mean of its divisors is an integer number (4305600).

Almost surely, 2^82666440 is an apocalyptic number.

It is an amenable number.

82666440 is an abundant number, since it is smaller than the sum of its proper divisors (192891960).

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

82666440 is a wasteful number, since it uses less digits than its factorization.

82666440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 76563 (or 76553 counting only the distinct ones).

The product of its (nonzero) digits is 55296, while the sum is 36.

The square root of 82666440 is about 9092.1086663106. The cubic root of 82666440 is about 435.6219403227.

It can be divided in two parts, 8266 and 6440, that added together give a triangular number (14706 = T₁₇₁).

The spelling of 82666440 in words is "eighty-two million, six hundred sixty-six thousand, four hundred forty".