1220603551 has 4 divisors (see below), whose sum is σ = 1220747992. Its totient is φ = 1220459112.

The previous prime is 1220603543. The next prime is 1220603557. The reversal of 1220603551 is 1553060221.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1553060221 = 12041 ⋅128981.

It is a cyclic number.

It is not a de Polignac number, because 1220603551 - 2³ = 1220603543 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 (1220603557) 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, 58701 + ... + 76726.

It is an arithmetic number, because the mean of its divisors is an integer number (305186998).

Almost surely, 2^1220603551 is an apocalyptic number.

1220603551 is a deficient number, since it is larger than the sum of its proper divisors (144441).

1220603551 is an equidigital number, since it uses as much as digits as its factorization.

1220603551 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 144440.

The product of its (nonzero) digits is 1800, while the sum is 25.

The square root of 1220603551 is about 34937.1371322837. The cubic root of 1220603551 is about 1068.7059066154.

Adding to 1220603551 its reverse (1553060221), we get a palindrome (2773663772).

The spelling of 1220603551 in words is "one billion, two hundred twenty million, six hundred three thousand, five hundred fifty-one".