1277791420 has 48 divisors (see below), whose sum is σ = 2830131360. Its totient is φ = 483266304.

The previous prime is 1277791373. The next prime is 1277791421. The reversal of 1277791420 is 241977721.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1277791421) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 208642 + ... + 214678.

It is an arithmetic number, because the mean of its divisors is an integer number (58961070).

Almost surely, 2^1277791420 is an apocalyptic number.

1277791420 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 1277791420, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1415065680).

1277791420 is an abundant number, since it is smaller than the sum of its proper divisors (1552339940).

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

1277791420 is a wasteful number, since it uses less digits than its factorization.

1277791420 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6622 (or 6620 counting only the distinct ones).

The product of its (nonzero) digits is 49392, while the sum is 40.

The square root of 1277791420 is about 35746.2084702700. The cubic root of 1277791420 is about 1085.1422070750.

The spelling of 1277791420 in words is "one billion, two hundred seventy-seven million, seven hundred ninety-one thousand, four hundred twenty".