1221420340997 has 16 divisors (see below), whose sum is σ = 1272624912000. Its totient is φ = 1170829101120.

The previous prime is 1221420340993. The next prime is 1221420341021. The reversal of 1221420340997 is 7990430241221.

It is not a de Polignac number, because 1221420340997 - 2² = 1221420340993 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1221420340993) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 9141728 + ... + 9274374.

It is an arithmetic number, because the mean of its divisors is an integer number (79539057000).

Almost surely, 2^{1221420340997} is an apocalyptic number.

It is an amenable number.

1221420340997 is a deficient number, since it is larger than the sum of its proper divisors (51204571003).

1221420340997 is a wasteful number, since it uses less digits than its factorization.

1221420340997 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 134956.

The product of its (nonzero) digits is 217728, while the sum is 44.

The spelling of 1221420340997 in words is "one trillion, two hundred twenty-one billion, four hundred twenty million, three hundred forty thousand, nine hundred ninety-seven".