1281012780 has 24 divisors (see below), whose sum is σ = 3586835952. Its totient is φ = 341603392.

The previous prime is 1281012757. The next prime is 1281012793. The reversal of 1281012780 is 872101821.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 10675047 + ... + 10675166.

It is an arithmetic number, because the mean of its divisors is an integer number (149451498).

Almost surely, 2^1281012780 is an apocalyptic number.

1281012780 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1281012780 is an abundant number, since it is smaller than the sum of its proper divisors (2305823172).

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

1281012780 is a wasteful number, since it uses less digits than its factorization.

1281012780 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21350225 (or 21350223 counting only the distinct ones).

The product of its (nonzero) digits is 1792, while the sum is 30.

The square root of 1281012780 is about 35791.2388721039. The cubic root of 1281012780 is about 1086.0533365473.

The spelling of 1281012780 in words is "one billion, two hundred eighty-one million, twelve thousand, seven hundred eighty".