1261920 has 96 divisors (see below), whose sum is σ = 4354560. Its totient is φ = 304640.

The previous prime is 1261913. The next prime is 1261933. The reversal of 1261920 is 291621.

It is a tau number, because it is divible by the number of its divisors (96).

It is an Ulam number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5161 + ... + 5399.

It is an arithmetic number, because the mean of its divisors is an integer number (45360).

2^1261920 is an apocalyptic number.

1261920 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 1261920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2177280).

1261920 is an abundant number, since it is smaller than the sum of its proper divisors (3092640).

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

1261920 is a wasteful number, since it uses less digits than its factorization.

1261920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 268 (or 260 counting only the distinct ones).

The product of its (nonzero) digits is 216, while the sum is 21.

The square root of 1261920 is about 1123.3521264501. The cubic root of 1261920 is about 108.0630633061.

Subtracting from 1261920 its reverse (291621), we obtain a cube (970299 = 99³).

The spelling of 1261920 in words is "one million, two hundred sixty-one thousand, nine hundred twenty".