1279920 has 40 divisors (see below), whose sum is σ = 3968496. Its totient is φ = 341248.

The previous prime is 1279919. The next prime is 1279921. The reversal of 1279920 is 299721.

It is an interprime number because it is at equal distance from previous prime (1279919) and next prime (1279921).

It is a tau number, because it is divible by the number of its divisors (40).

It is a Smith number, since the sum of its digits (30) coincides with the sum of the digits of its prime factors.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is not an unprimeable number, because it can be changed into a prime (1279921) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2427 + ... + 2906.

2^1279920 is an apocalyptic number.

1279920 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1279920 is an abundant number, since it is smaller than the sum of its proper divisors (2688576).

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

1279920 is a wasteful number, since it uses less digits than its factorization.

1279920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5349 (or 5343 counting only the distinct ones).

The product of its (nonzero) digits is 2268, while the sum is 30.

The square root of 1279920 is about 1131.3354940070. The cubic root of 1279920 is about 108.5744426020.

The spelling of 1279920 in words is "one million, two hundred seventy-nine thousand, nine hundred twenty".