1211201997 has 4 divisors (see below), whose sum is σ = 1614936000. Its totient is φ = 807467996.

The previous prime is 1211201989. The next prime is 1211202007. The reversal of 1211201997 is 7991021121.

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 not a de Polignac number, because 1211201997 - 2³ = 1211201989 is a prime.

It is a super-3 number, since 3×1211201997³ (a number of 28 digits) contains 333 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1211201917) 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, 201866997 + ... + 201867002.

It is an arithmetic number, because the mean of its divisors is an integer number (403734000).

Almost surely, 2^1211201997 is an apocalyptic number.

It is an amenable number.

1211201997 is a deficient number, since it is larger than the sum of its proper divisors (403734003).

1211201997 is an equidigital number, since it uses as much as digits as its factorization.

1211201997 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 403734002.

The product of its (nonzero) digits is 2268, while the sum is 33.

The square root of 1211201997 is about 34802.3274652716. The cubic root of 1211201997 is about 1065.9549714221.

The spelling of 1211201997 in words is "one billion, two hundred eleven million, two hundred one thousand, nine hundred ninety-seven".