81850776 has 128 divisors (see below), whose sum is σ = 244032000. Its totient is φ = 22861440.

The previous prime is 81850753. The next prime is 81850799. The reversal of 81850776 is 67705818.

It is an interprime number because it is at equal distance from previous prime (81850753) and next prime (81850799).

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 502071 + ... + 502233.

It is an arithmetic number, because the mean of its divisors is an integer number (1906500).

Almost surely, 2^81850776 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 81850776, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (122016000).

81850776 is an abundant number, since it is smaller than the sum of its proper divisors (162181224).

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

81850776 is a wasteful number, since it uses less digits than its factorization.

81850776 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 254 (or 236 counting only the distinct ones).

The product of its (nonzero) digits is 94080, while the sum is 42.

The square root of 81850776 is about 9047.1418691209. The cubic root of 81850776 is about 434.1844515998.

The spelling of 81850776 in words is "eighty-one million, eight hundred fifty thousand, seven hundred seventy-six".