201081990 has 16 divisors (see below), whose sum is σ = 482596848. Its totient is φ = 53621856.

The previous prime is 201081961. The next prime is 201082009. The reversal of 201081990 is 99180102.

201081990 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (30), and also a Moran number because the ratio is a prime number: 6702733 = 201081990 / (2 + 0 + 1 + 0 + 8 + 1 + 9 + 9 + 0).

It is a Curzon number.

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, 3351337 + ... + 3351396.

It is an arithmetic number, because the mean of its divisors is an integer number (30162303).

Almost surely, 2^201081990 is an apocalyptic number.

201081990 is an abundant number, since it is smaller than the sum of its proper divisors (281514858).

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

201081990 is a wasteful number, since it uses less digits than its factorization.

201081990 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6702743.

The product of its (nonzero) digits is 1296, while the sum is 30.

The square root of 201081990 is about 14180.3381482953. The cubic root of 201081990 is about 585.8562375695.

The spelling of 201081990 in words is "two hundred one million, eighty-one thousand, nine hundred ninety".