1275633889920 has 768 divisors, whose sum is σ = 5109905848320. Its totient is φ = 290649047040.

The previous prime is 1275633889883. The next prime is 1275633889927. The reversal of 1275633889920 is 299883365721.

1275633889920 is a `hidden beast` number, since 1 + 275 + 6 + 338 + 8 + 9 + 9 + 20 = 666.

It is a super-2 number, since 2×1275633889920² (a number of 25 digits) contains 22 as substring.

It is a Smith number, since the sum of its digits (63) coincides with the sum of the digits of its prime factors.

It is not an unprimeable number, because it can be changed into a prime (1275633889927) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 53377494 + ... + 53401386.

It is an arithmetic number, because the mean of its divisors is an integer number (6653523240).

Almost surely, 2^{1275633889920} is an apocalyptic number.

1275633889920 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 1275633889920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2554952924160).

1275633889920 is an abundant number, since it is smaller than the sum of its proper divisors (3834271958400).

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

1275633889920 is a wasteful number, since it uses less digits than its factorization.

1275633889920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23985 (or 23970 counting only the distinct ones).

The product of its (nonzero) digits is 39191040, while the sum is 63.

The spelling of 1275633889920 in words is "one trillion, two hundred seventy-five billion, six hundred thirty-three million, eight hundred eighty-nine thousand, nine hundred twenty".