90609840 has 240 divisors, whose sum is σ = 324979200. Its totient is φ = 23452416.

The previous prime is 90609829. The next prime is 90609851. The reversal of 90609840 is 4890609.

90609840 is a `hidden beast` number, since 9 + 0 + 609 + 8 + 40 = 666.

It is an interprime number because it is at equal distance from previous prime (90609829) and next prime (90609851).

It is a tau number, because it is divible by the number of its divisors (240).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 90609795 and 90609804.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 1146921 + ... + 1146999.

It is an arithmetic number, because the mean of its divisors is an integer number (1354080).

Almost surely, 2^90609840 is an apocalyptic number.

90609840 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 90609840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (162489600).

90609840 is an abundant number, since it is smaller than the sum of its proper divisors (234369360).

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

90609840 is a wasteful number, since it uses less digits than its factorization.

90609840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 166 (or 148 counting only the distinct ones).

The product of its (nonzero) digits is 15552, while the sum is 36.

The square root of 90609840 is about 9518.9201068188. The cubic root of 90609840 is about 449.1503969532.

The spelling of 90609840 in words is "ninety million, six hundred nine thousand, eight hundred forty".