1231378272 has 144 divisors (see below), whose sum is σ = 3794590800. Its totient is φ = 377266176.

The previous prime is 1231378271. The next prime is 1231378283. The reversal of 1231378272 is 2728731321.

1231378272 is a `hidden beast` number, since 1 + 2 + 313 + 78 + 272 = 666.

It is a tau number, because it is divible by the number of its divisors (144).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1231378271) 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, 207604 + ... + 213452.

It is an arithmetic number, because the mean of its divisors is an integer number (26351325).

Almost surely, 2^1231378272 is an apocalyptic number.

1231378272 is a gapful number since it is divisible by the number (12) 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 1231378272, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1897295400).

1231378272 is an abundant number, since it is smaller than the sum of its proper divisors (2563212528).

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

1231378272 is a wasteful number, since it uses less digits than its factorization.

1231378272 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5925 (or 5914 counting only the distinct ones).

The product of its digits is 28224, while the sum is 36.

The square root of 1231378272 is about 35090.9998717620. Note that the first 3 decimals coincide. The cubic root of 1231378272 is about 1071.8413201679.

The spelling of 1231378272 in words is "one billion, two hundred thirty-one million, three hundred seventy-eight thousand, two hundred seventy-two".