1268019840 has 128 divisors (see below), whose sum is σ = 4058392320. Its totient is φ = 336752640.

The previous prime is 1268019839. The next prime is 1268019847. The reversal of 1268019840 is 489108621.

It is a tau number, because it is divible by the number of its divisors (128).

It is not an unprimeable number, because it can be changed into a prime (1268019847) 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, 519102 + ... + 521538.

It is an arithmetic number, because the mean of its divisors is an integer number (31706190).

Almost surely, 2^1268019840 is an apocalyptic number.

1268019840 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 1268019840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2029196160).

1268019840 is an abundant number, since it is smaller than the sum of its proper divisors (2790372480).

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

1268019840 is a wasteful number, since it uses less digits than its factorization.

1268019840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2730 (or 2718 counting only the distinct ones).

The product of its (nonzero) digits is 27648, while the sum is 39.

The square root of 1268019840 is about 35609.2662097943. The cubic root of 1268019840 is about 1082.3690109553.

The spelling of 1268019840 in words is "one billion, two hundred sixty-eight million, nineteen thousand, eight hundred forty".