1221200997 has 8 divisors (see below), whose sum is σ = 1645054656. Its totient is φ = 805740672.

The previous prime is 1221200993. The next prime is 1221201019. The reversal of 1221200997 is 7990021221.

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

It is not a de Polignac number, because 1221200997 - 2² = 1221200993 is a prime.

It is a super-4 number, since 4×1221200997⁴ (a number of 37 digits) contains 4444 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1221200993) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2097993 + ... + 2098574.

It is an arithmetic number, because the mean of its divisors is an integer number (205631832).

Almost surely, 2^1221200997 is an apocalyptic number.

It is an amenable number.

1221200997 is a deficient number, since it is larger than the sum of its proper divisors (423853659).

1221200997 is an equidigital number, since it uses as much as digits as its factorization.

1221200997 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4196667.

The product of its (nonzero) digits is 4536, while the sum is 33.

The square root of 1221200997 is about 34945.6863861622. The cubic root of 1221200997 is about 1068.8802438446.

The spelling of 1221200997 in words is "one billion, two hundred twenty-one million, two hundred thousand, nine hundred ninety-seven".