1288690 has 32 divisors (see below), whose sum is σ = 2612736. Its totient is φ = 454080.

The previous prime is 1288657. The next prime is 1288691. The reversal of 1288690 is 968821.

It is a super-2 number, since 2×1288690² = 3321443832200, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1288691) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2775 + ... + 3205.

It is an arithmetic number, because the mean of its divisors is an integer number (81648).

2^1288690 is an apocalyptic number.

1288690 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1288690 is an abundant number, since it is smaller than the sum of its proper divisors (1324046).

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

1288690 is a wasteful number, since it uses less digits than its factorization.

1288690 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 474.

The product of its (nonzero) digits is 6912, while the sum is 34.

The square root of 1288690 is about 1135.2048273329. The cubic root of 1288690 is about 108.8218620464.

The spelling of 1288690 in words is "one million, two hundred eighty-eight thousand, six hundred ninety".