81474680 has 128 divisors (see below), whose sum is σ = 219732480. Its totient is φ = 26611200.

The previous prime is 81474677. The next prime is 81474689. The reversal of 81474680 is 8647418.

It is a super-2 number, since 2×81474680² = 13276246962204800, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81474689) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 806630 + ... + 806730.

It is an arithmetic number, because the mean of its divisors is an integer number (1716660).

Almost surely, 2^81474680 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 81474680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (109866240).

81474680 is an abundant number, since it is smaller than the sum of its proper divisors (138257800).

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

81474680 is a wasteful number, since it uses less digits than its factorization.

81474680 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 229 (or 225 counting only the distinct ones).

The product of its (nonzero) digits is 43008, while the sum is 38.

The square root of 81474680 is about 9026.3325885988. The cubic root of 81474680 is about 433.5184192909.

The spelling of 81474680 in words is "eighty-one million, four hundred seventy-four thousand, six hundred eighty".