81087798 has 16 divisors (see below), whose sum is σ = 176918976. Its totient is φ = 24572040.

The previous prime is 81087779. The next prime is 81087817. The reversal of 81087798 is 89778018.

It is an interprime number because it is at equal distance from previous prime (81087779) and next prime (81087817).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 614236 + ... + 614367.

It is an arithmetic number, because the mean of its divisors is an integer number (11057436).

Almost surely, 2^81087798 is an apocalyptic number.

81087798 is an abundant number, since it is smaller than the sum of its proper divisors (95831178).

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

81087798 is a wasteful number, since it uses less digits than its factorization.

81087798 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1228619.

The product of its (nonzero) digits is 225792, while the sum is 48.

The square root of 81087798 is about 9004.8763456252. The cubic root of 81087798 is about 432.8311438132.

The spelling of 81087798 in words is "eighty-one million, eighty-seven thousand, seven hundred ninety-eight".