72090000 has 250 divisors, whose sum is σ = 263657790. Its totient is φ = 19008000.

The previous prime is 72089999. The next prime is 72090019. The reversal of 72090000 is 9027.

It can be written as a sum of positive squares in 5 ways, for example, as 40144896 + 31945104 = 6336^2 + 5652^2 .

It is a tau number, because it is divible by the number of its divisors (250).

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

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 49 ways as a sum of consecutive naturals, for example, 809956 + ... + 810044.

Almost surely, 2^72090000 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 72090000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (131828895).

72090000 is an abundant number, since it is smaller than the sum of its proper divisors (191567790).

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

72090000 is an equidigital number, since it uses as much as digits as its factorization.

72090000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 129 (or 99 counting only the distinct ones).

The product of its (nonzero) digits is 126, while the sum is 18.

The square root of 72090000 is about 8490.5830188509. The cubic root of 72090000 is about 416.1900327540.

Adding to 72090000 its reverse (9027), we get a palindrome (72099027).

The spelling of 72090000 in words is "seventy-two million, ninety thousand".