1284120640 has 112 divisors (see below), whose sum is σ = 3346850304. Its totient is φ = 465408000.

The previous prime is 1284120601. The next prime is 1284120671. The reversal of 1284120640 is 460214821.

It is a junction number, because it is equal to n+sod(n) for n = 1284120599 and 1284120608.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2115217 + ... + 2115823.

It is an arithmetic number, because the mean of its divisors is an integer number (29882592).

Almost surely, 2^1284120640 is an apocalyptic number.

1284120640 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 1284120640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1673425152).

1284120640 is an abundant number, since it is smaller than the sum of its proper divisors (2062729664).

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

1284120640 is a wasteful number, since it uses less digits than its factorization.

1284120640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1236 (or 1226 counting only the distinct ones).

The product of its (nonzero) digits is 3072, while the sum is 28.

The square root of 1284120640 is about 35834.6290618446. The cubic root of 1284120640 is about 1086.9309171216.

The spelling of 1284120640 in words is "one billion, two hundred eighty-four million, one hundred twenty thousand, six hundred forty".