81267616 has 96 divisors (see below), whose sum is σ = 179988480. Its totient is φ = 35942400.

The previous prime is 81267587. The next prime is 81267623. The reversal of 81267616 is 61676218.

It is a hoax number, since the sum of its digits (37) coincides with the sum of the digits of its distinct prime factors.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1028665 + ... + 1028743.

It is an arithmetic number, because the mean of its divisors is an integer number (1874880).

Almost surely, 2^81267616 is an apocalyptic number.

81267616 is the 4819-th nonagonal number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 81267616, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (89994240).

81267616 is an abundant number, since it is smaller than the sum of its proper divisors (98720864).

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

81267616 is a wasteful number, since it uses less digits than its factorization.

81267616 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 198 (or 190 counting only the distinct ones).

The product of its digits is 24192, while the sum is 37.

The square root of 81267616 is about 9014.8552955663. The cubic root of 81267616 is about 433.1508522918.

The spelling of 81267616 in words is "eighty-one million, two hundred sixty-seven thousand, six hundred sixteen".