1990423512 has 384 divisors, whose sum is σ = 7278336000. Its totient is φ = 485452800.

The previous prime is 1990423511. The next prime is 1990423531. The reversal of 1990423512 is 2153240991.

1990423512 is a `hidden beast` number, since 19 + 90 + 42 + 3 + 512 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1990423511) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 4617937 + ... + 4618367.

It is an arithmetic number, because the mean of its divisors is an integer number (18954000).

Almost surely, 2^1990423512 is an apocalyptic number.

1990423512 is a gapful number since it is divisible by the number (12) 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 1990423512, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3639168000).

1990423512 is an abundant number, since it is smaller than the sum of its proper divisors (5287912488).

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

1990423512 is a wasteful number, since it uses less digits than its factorization.

1990423512 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 492 (or 471 counting only the distinct ones).

The product of its (nonzero) digits is 19440, while the sum is 36.

The square root of 1990423512 is about 44614.1626840626. The cubic root of 1990423512 is about 1257.9068952421.

The spelling of 1990423512 in words is "one billion, nine hundred ninety million, four hundred twenty-three thousand, five hundred twelve".