1551223120 has 20 divisors (see below), whose sum is σ = 3606593940. Its totient is φ = 620489216.

The previous prime is 1551223073. The next prime is 1551223139. The reversal of 1551223120 is 213221551.

It can be written as a sum of positive squares in 2 ways, for example, as 1050537744 + 500685376 = 32412^2 + 22376^2 .

It is a tau number, because it is divible by the number of its divisors (20).

It is a junction number, because it is equal to n+sod(n) for n = 1551223091 and 1551223100.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9695065 + ... + 9695224.

It is an arithmetic number, because the mean of its divisors is an integer number (180329697).

Almost surely, 2^1551223120 is an apocalyptic number.

1551223120 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1551223120 is an abundant number, since it is smaller than the sum of its proper divisors (2055370820).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1551223120 is a wasteful number, since it uses less digits than its factorization.

1551223120 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19390302 (or 19390296 counting only the distinct ones).

The product of its (nonzero) digits is 600, while the sum is 22.

The square root of 1551223120 is about 39385.5699463649. The cubic root of 1551223120 is about 1157.5988579972.

Adding to 1551223120 its reverse (213221551), we get a palindrome (1764444671).

The spelling of 1551223120 in words is "one billion, five hundred fifty-one million, two hundred twenty-three thousand, one hundred twenty".