1266384538400 has 72 divisors (see below), whose sum is σ = 3093567873984. Its totient is φ = 506225030400.

The previous prime is 1266384538399. The next prime is 1266384538453. The reversal of 1266384538400 is 48354836621.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (50).

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 721445 + ... + 1747355.

It is an arithmetic number, because the mean of its divisors is an integer number (42966220472).

Almost surely, 2^{1266384538400} is an apocalyptic number.

1266384538400 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 1266384538400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1546783936992).

1266384538400 is an abundant number, since it is smaller than the sum of its proper divisors (1827183335584).

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

1266384538400 is a wasteful number, since it uses less digits than its factorization.

1266384538400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1027474 (or 1027461 counting only the distinct ones).

The product of its (nonzero) digits is 3317760, while the sum is 50.

The spelling of 1266384538400 in words is "one trillion, two hundred sixty-six billion, three hundred eighty-four million, five hundred thirty-eight thousand, four hundred".