1273489920 has 240 divisors, whose sum is σ = 4555279872. Its totient is φ = 328458240.

The previous prime is 1273489909. The next prime is 1273489927. The reversal of 1273489920 is 299843721.

1273489920 is a `hidden beast` number, since 12 + 73 + 489 + 92 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (240).

It is a Harshad number since it is a multiple of its sum of digits (45).

It is not an unprimeable number, because it can be changed into a prime (1273489927) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 713349 + ... + 715131.

Almost surely, 2^1273489920 is an apocalyptic number.

1273489920 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 1273489920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2277639936).

1273489920 is an abundant number, since it is smaller than the sum of its proper divisors (3281789952).

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

1273489920 is a wasteful number, since it uses less digits than its factorization.

1273489920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1843 (or 1824 counting only the distinct ones).

The product of its (nonzero) digits is 217728, while the sum is 45.

The square root of 1273489920 is about 35685.9905284973. The cubic root of 1273489920 is about 1083.9231800610.

The spelling of 1273489920 in words is "one billion, two hundred seventy-three million, four hundred eighty-nine thousand, nine hundred twenty".