1251990 has 32 divisors (see below), whose sum is σ = 3339360. Its totient is φ = 333792.

The previous prime is 1251983. The next prime is 1252021. The reversal of 1251990 is 991521.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2049 + ... + 2588.

It is an arithmetic number, because the mean of its divisors is an integer number (104355).

2^1251990 is an apocalyptic number.

1251990 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1251990 is an abundant number, since it is smaller than the sum of its proper divisors (2087370).

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

1251990 is a wasteful number, since it uses less digits than its factorization.

1251990 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4653 (or 4647 counting only the distinct ones).

The product of its (nonzero) digits is 810, while the sum is 27.

The square root of 1251990 is about 1118.9235898845. The cubic root of 1251990 is about 107.7788685270.

The spelling of 1251990 in words is "one million, two hundred fifty-one thousand, nine hundred ninety".