1221850697 has 4 divisors (see below), whose sum is σ = 1222115856. Its totient is φ = 1221585540.

The previous prime is 1221850691. The next prime is 1221850699. The reversal of 1221850697 is 7960581221.

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 1221850697 - 2¹² = 1221846601 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1221850691) 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, 125543 + ... + 134924.

It is an arithmetic number, because the mean of its divisors is an integer number (305528964).

Almost surely, 2^1221850697 is an apocalyptic number.

It is an amenable number.

1221850697 is a deficient number, since it is larger than the sum of its proper divisors (265159).

1221850697 is an equidigital number, since it uses as much as digits as its factorization.

1221850697 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 265158.

The product of its (nonzero) digits is 60480, while the sum is 41.

The square root of 1221850697 is about 34954.9810041430. The cubic root of 1221850697 is about 1069.0697644830.

The spelling of 1221850697 in words is "one billion, two hundred twenty-one million, eight hundred fifty thousand, six hundred ninety-seven".