1286731980 has 120 divisors (see below), whose sum is σ = 4145814288. Its totient is φ = 333839232.

The previous prime is 1286731937. The next prime is 1286731981. The reversal of 1286731980 is 891376821.

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 (1286731981) by changing a digit.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 49207 + ... + 70673.

Almost surely, 2^1286731980 is an apocalyptic number.

1286731980 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 1286731980, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2072907144).

1286731980 is an abundant number, since it is smaller than the sum of its proper divisors (2859082308).

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

1286731980 is a wasteful number, since it uses less digits than its factorization.

1286731980 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21525 (or 21514 counting only the distinct ones).

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

The square root of 1286731980 is about 35871.0465417445. The cubic root of 1286731980 is about 1087.6671990249.

The spelling of 1286731980 in words is "one billion, two hundred eighty-six million, seven hundred thirty-one thousand, nine hundred eighty".