90195840 has 192 divisors, whose sum is σ = 356110560. Its totient is φ = 20606976.

The previous prime is 90195839. The next prime is 90195841. The reversal of 90195840 is 4859109.

It is an interprime number because it is at equal distance from previous prime (90195839) and next prime (90195841).

It is a tau number, because it is divible by the number of its divisors (192).

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 = 90195795 and 90195804.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (90195841) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 39202 + ... + 41438.

Almost surely, 2^90195840 is an apocalyptic number.

90195840 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 90195840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (178055280).

90195840 is an abundant number, since it is smaller than the sum of its proper divisors (265914720).

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

90195840 is a wasteful number, since it uses less digits than its factorization.

90195840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2269 (or 2254 counting only the distinct ones).

The product of its (nonzero) digits is 12960, while the sum is 36.

The square root of 90195840 is about 9497.1490458979. The cubic root of 90195840 is about 448.4652903941.

The spelling of 90195840 in words is "ninety million, one hundred ninety-five thousand, eight hundred forty".