1221745607 has 4 divisors (see below), whose sum is σ = 1222870656. Its totient is φ = 1220620560.

The previous prime is 1221745601. The next prime is 1221745621. The reversal of 1221745607 is 7065471221.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 7065471221 = 73 ⋅96787277.

It is a cyclic number.

It is not a de Polignac number, because 1221745607 - 2²² = 1217551303 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 (1221745601) 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, 560894 + ... + 563067.

It is an arithmetic number, because the mean of its divisors is an integer number (305717664).

Almost surely, 2^1221745607 is an apocalyptic number.

1221745607 is a deficient number, since it is larger than the sum of its proper divisors (1125049).

1221745607 is a wasteful number, since it uses less digits than its factorization.

1221745607 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1125048.

The product of its (nonzero) digits is 23520, while the sum is 35.

The square root of 1221745607 is about 34953.4777525785. The cubic root of 1221745607 is about 1069.0391137761.

The spelling of 1221745607 in words is "one billion, two hundred twenty-one million, seven hundred forty-five thousand, six hundred seven".