91080000 has 420 divisors, whose sum is σ = 371356128. Its totient is φ = 21120000.

The previous prime is 91079987. The next prime is 91080037. The reversal of 91080000 is 8019.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 59 ways as a sum of consecutive naturals, for example, 3959989 + ... + 3960011.

Almost surely, 2^91080000 is an apocalyptic number.

91080000 is a gapful number since it is divisible by the number (90) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 91080000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (185678064).

91080000 is an abundant number, since it is smaller than the sum of its proper divisors (280276128).

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

91080000 is a wasteful number, since it uses less digits than its factorization.

91080000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 72 (or 44 counting only the distinct ones).

The product of its (nonzero) digits is 72, while the sum is 18.

The square root of 91080000 is about 9543.5842323521. The cubic root of 91080000 is about 449.9259137293.

Adding to 91080000 its reverse (8019), we get a palindrome (91088019).

The spelling of 91080000 in words is "ninety-one million, eighty thousand".