1279720 has 64 divisors (see below), whose sum is σ = 3265920. Its totient is φ = 447744.

The previous prime is 1279703. The next prime is 1279727. The reversal of 1279720 is 279721.

It is a happy number.

It is a Smith number, since the sum of its digits (28) coincides with the sum of the digits of its prime factors.

It is not an unprimeable number, because it can be changed into a prime (1279727) 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, 11907 + ... + 12013.

It is an arithmetic number, because the mean of its divisors is an integer number (51030).

2^1279720 is an apocalyptic number.

1279720 is a gapful number since it is divisible by the number (10) 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 1279720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1632960).

1279720 is an abundant number, since it is smaller than the sum of its proper divisors (1986200).

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

1279720 is a wasteful number, since it uses less digits than its factorization.

1279720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 154 (or 150 counting only the distinct ones).

The product of its (nonzero) digits is 1764, while the sum is 28.

The square root of 1279720 is about 1131.2470994438. The cubic root of 1279720 is about 108.5687870351.

Subtracting from 1279720 its reverse (279721), we obtain a palindrome (999999).

The spelling of 1279720 in words is "one million, two hundred seventy-nine thousand, seven hundred twenty".