201023640 has 128 divisors (see below), whose sum is σ = 709560000. Its totient is φ = 50448384.

The previous prime is 201023597. The next prime is 201023663. The reversal of 201023640 is 46320102.

It is a happy number.

201023640 is a `hidden beast` number, since 2 + 0 + 1 + 0 + 23 + 640 = 666.

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 31 ways as a sum of consecutive naturals, for example, 12886 + ... + 23834.

Almost surely, 2^201023640 is an apocalyptic number.

201023640 is a gapful number since it is divisible by the number (20) 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 201023640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (354780000).

201023640 is an abundant number, since it is smaller than the sum of its proper divisors (508536360).

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

201023640 is a wasteful number, since it uses less digits than its factorization.

201023640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10986 (or 10976 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 18.

The square root of 201023640 is about 14178.2805727634. The cubic root of 201023640 is about 585.7995641390.

Adding to 201023640 its reverse (46320102), we get a palindrome (247343742).

The spelling of 201023640 in words is "two hundred one million, twenty-three thousand, six hundred forty".