1280661632100 has 144 divisors (see below), whose sum is σ = 4155568401600. Its totient is φ = 338318012160.

The previous prime is 1280661632053. The next prime is 1280661632119. The reversal of 1280661632100 is 12361660821.

It is a happy number.

1280661632100 is a `hidden beast` number, since 1 + 2 + 8 + 0 + 6 + 6 + 1 + 632 + 10 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 1927545 + ... + 2505344.

It is an arithmetic number, because the mean of its divisors is an integer number (28858113900).

Almost surely, 2^{1280661632100} is an apocalyptic number.

1280661632100 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1280661632100 is an abundant number, since it is smaller than the sum of its proper divisors (2874906769500).

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

1280661632100 is a wasteful number, since it uses less digits than its factorization.

1280661632100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4433019 (or 4433006 counting only the distinct ones).

The product of its (nonzero) digits is 20736, while the sum is 36.

The spelling of 1280661632100 in words is "one trillion, two hundred eighty billion, six hundred sixty-one million, six hundred thirty-two thousand, one hundred".