1221100332013 has 4 divisors (see below), whose sum is σ = 1285368770560. Its totient is φ = 1156831893468.

The previous prime is 1221100331993. The next prime is 1221100332041. The reversal of 1221100332013 is 3102330011221.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1221100332013 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (19), and also a Moran number because the ratio is a prime number: 64268438527 = 1221100332013 / (1 + 2 + 2 + 1 + 1 + 0 + 0 + 3 + 3 + 2 + 0 + 1 + 3).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1221100332043) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 32134219245 + ... + 32134219282.

It is an arithmetic number, because the mean of its divisors is an integer number (321342192640).

Almost surely, 2^{1221100332013} is an apocalyptic number.

It is an amenable number.

1221100332013 is a deficient number, since it is larger than the sum of its proper divisors (64268438547).

1221100332013 is an equidigital number, since it uses as much as digits as its factorization.

1221100332013 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 64268438546.

The product of its (nonzero) digits is 216, while the sum is 19.

Adding to 1221100332013 its reverse (3102330011221), we get a palindrome (4323430343234).

The spelling of 1221100332013 in words is "one trillion, two hundred twenty-one billion, one hundred million, three hundred thirty-two thousand, thirteen".