1309777920 has 672 divisors, whose sum is σ = 5520415680. Its totient is φ = 283115520.

The previous prime is 1309777913. The next prime is 1309777927. The reversal of 1309777920 is 297779031.

It is an interprime number because it is at equal distance from previous prime (1309777913) and next prime (1309777927).

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 (1309777927) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 68935671 + ... + 68935689.

Almost surely, 2^1309777920 is an apocalyptic number.

1309777920 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 1309777920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2760207840).

1309777920 is an abundant number, since it is smaller than the sum of its proper divisors (4210637760).

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

1309777920 is a wasteful number, since it uses less digits than its factorization.

1309777920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 84 (or 57 counting only the distinct ones).

The product of its (nonzero) digits is 166698, while the sum is 45.

The square root of 1309777920 is about 36190.8540932651. The cubic root of 1309777920 is about 1094.1223467183.

The spelling of 1309777920 in words is "one billion, three hundred nine million, seven hundred seventy-seven thousand, nine hundred twenty".