1287996090 has 128 divisors (see below), whose sum is σ = 3332358144. Its totient is φ = 317856000.

The previous prime is 1287996077. The next prime is 1287996121. The reversal of 1287996090 is 906997821.

It is a happy number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 2988175 + ... + 2988605.

It is an arithmetic number, because the mean of its divisors is an integer number (26034048).

Almost surely, 2^1287996090 is an apocalyptic number.

1287996090 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 1287996090, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1666179072).

1287996090 is an abundant number, since it is smaller than the sum of its proper divisors (2044362054).

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

1287996090 is a wasteful number, since it uses less digits than its factorization.

1287996090 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 596.

The product of its (nonzero) digits is 489888, while the sum is 51.

The square root of 1287996090 is about 35888.6624158661. The cubic root of 1287996090 is about 1088.0232641048.

The spelling of 1287996090 in words is "one billion, two hundred eighty-seven million, nine hundred ninety-six thousand, ninety".