203980491990 has 576 divisors, whose sum is σ = 642540330432. Its totient is φ = 44670320640.

The previous prime is 203980491937. The next prime is 203980491997. The reversal of 203980491990 is 99194089302.

203980491990 is a `hidden beast` number, since 20 + 398 + 0 + 49 + 199 + 0 = 666.

It is a super-2 number, since 2×203980491990² (a number of 23 digits) contains 22 as substring.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (203980491997) by changing a digit.

It is a polite number, since it can be written in 287 ways as a sum of consecutive naturals, for example, 664431417 + ... + 664431723.

It is an arithmetic number, because the mean of its divisors is an integer number (1115521407).

Almost surely, 2^203980491990 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 203980491990, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (321270165216).

203980491990 is an abundant number, since it is smaller than the sum of its proper divisors (438559838442).

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

203980491990 is a wasteful number, since it uses less digits than its factorization.

203980491990 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 493 (or 479 counting only the distinct ones).

The product of its (nonzero) digits is 1259712, while the sum is 54.

The spelling of 203980491990 in words is "two hundred three billion, nine hundred eighty million, four hundred ninety-one thousand, nine hundred ninety".