1221100019975 has 24 divisors (see below), whose sum is σ = 1705099676160. Its totient is φ = 859425228000.

The previous prime is 1221100019941. The next prime is 1221100019977. The reversal of 1221100019975 is 5799100011221.

It is not a de Polignac number, because 1221100019975 - 2⁶ = 1221100019911 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1221100019977) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 71610245 + ... + 71627294.

It is an arithmetic number, because the mean of its divisors is an integer number (71045819840).

Almost surely, 2^{1221100019975} is an apocalyptic number.

1221100019975 is a deficient number, since it is larger than the sum of its proper divisors (483999656185).

1221100019975 is a wasteful number, since it uses less digits than its factorization.

1221100019975 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 143237591 (or 143237586 counting only the distinct ones).

The product of its (nonzero) digits is 11340, while the sum is 38.

The spelling of 1221100019975 in words is "one trillion, two hundred twenty-one billion, one hundred million, nineteen thousand, nine hundred seventy-five".