1320235551 has 16 divisors (see below), whose sum is σ = 1964308320. Its totient is φ = 876375360.

The previous prime is 1320235519. The next prime is 1320235561. The reversal of 1320235551 is 1555320231.

It is a happy number.

It is not a de Polignac number, because 1320235551 - 2⁵ = 1320235519 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1320235561) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 98640 + ... + 111221.

It is an arithmetic number, because the mean of its divisors is an integer number (122769270).

Almost surely, 2^1320235551 is an apocalyptic number.

1320235551 is a deficient number, since it is larger than the sum of its proper divisors (644072769).

1320235551 is a wasteful number, since it uses less digits than its factorization.

1320235551 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 210103 (or 210097 counting only the distinct ones).

The product of its (nonzero) digits is 4500, while the sum is 27.

The square root of 1320235551 is about 36335.0457685139. The cubic root of 1320235551 is about 1097.0265566899.

Adding to 1320235551 its reverse (1555320231), we get a palindrome (2875555782).

The spelling of 1320235551 in words is "one billion, three hundred twenty million, two hundred thirty-five thousand, five hundred fifty-one".