1221089137 has 8 divisors (see below), whose sum is σ = 1246746816. Its totient is φ = 1195650192.

The previous prime is 1221089057. The next prime is 1221089171. The reversal of 1221089137 is 7319801221.

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

It is a cyclic number.

It is not a de Polignac number, because 1221089137 - 2²³ = 1212700529 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1221089197) 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, 43378 + ... + 65755.

It is an arithmetic number, because the mean of its divisors is an integer number (155843352).

Almost surely, 2^1221089137 is an apocalyptic number.

It is an amenable number.

1221089137 is a deficient number, since it is larger than the sum of its proper divisors (25657679).

1221089137 is a wasteful number, since it uses less digits than its factorization.

1221089137 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 109367.

The product of its (nonzero) digits is 6048, while the sum is 34.

The square root of 1221089137 is about 34944.0858658515. The cubic root of 1221089137 is about 1068.8476069582.

The spelling of 1221089137 in words is "one billion, two hundred twenty-one million, eighty-nine thousand, one hundred thirty-seven".