1221331012078 has 8 divisors (see below), whose sum is σ = 1833943382280. Its totient is φ = 610016551320.

The previous prime is 1221331012067. The next prime is 1221331012079. The reversal of 1221331012078 is 8702101331221.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1221331012079) 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, 324475008 + ... + 324478771.

It is an arithmetic number, because the mean of its divisors is an integer number (229242922785).

Almost surely, 2^{1221331012078} is an apocalyptic number.

1221331012078 is a deficient number, since it is larger than the sum of its proper divisors (612612370202).

1221331012078 is an equidigital number, since it uses as much as digits as its factorization.

1221331012078 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 648954722.

The product of its (nonzero) digits is 4032, while the sum is 31.

Adding to 1221331012078 its reverse (8702101331221), we get a palindrome (9923432343299).

The spelling of 1221331012078 in words is "one trillion, two hundred twenty-one billion, three hundred thirty-one million, twelve thousand, seventy-eight".