1309861872 has 120 divisors (see below), whose sum is σ = 4092261888. Its totient is φ = 387676800.

The previous prime is 1309861867. The next prime is 1309861873. The reversal of 1309861872 is 2781689031.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1309861873) 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, 58497 + ... + 77727.

Almost surely, 2^1309861872 is an apocalyptic number.

1309861872 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 1309861872, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2046130944).

1309861872 is an abundant number, since it is smaller than the sum of its proper divisors (2782400016).

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

1309861872 is a wasteful number, since it uses less digits than its factorization.

1309861872 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19299 (or 19290 counting only the distinct ones).

The product of its (nonzero) digits is 145152, while the sum is 45.

The square root of 1309861872 is about 36192.0139257268. The cubic root of 1309861872 is about 1094.1457226396.

The spelling of 1309861872 in words is "one billion, three hundred nine million, eight hundred sixty-one thousand, eight hundred seventy-two".