1551323213 has 6 divisors (see below), whose sum is σ = 1705173582. Its totient is φ = 1410293720.

The previous prime is 1551323209. The next prime is 1551323227. The reversal of 1551323213 is 3123231551.

It can be written as a sum of positive squares in only one way, i.e., 1549052164 + 2271049 = 39358^2 + 1507^2 .

It is not a de Polignac number, because 1551323213 - 2² = 1551323209 is a prime.

It is a super-2 number, since 2×1551323213² = 4813207422385286738, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1551323413) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 6410306 + ... + 6410547.

It is an arithmetic number, because the mean of its divisors is an integer number (284195597).

Almost surely, 2^1551323213 is an apocalyptic number.

It is an amenable number.

1551323213 is a deficient number, since it is larger than the sum of its proper divisors (153850369).

1551323213 is a wasteful number, since it uses less digits than its factorization.

1551323213 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12820875 (or 12820864 counting only the distinct ones).

The product of its digits is 2700, while the sum is 26.

The square root of 1551323213 is about 39386.8406069845. The cubic root of 1551323213 is about 1157.6237555655.

Adding to 1551323213 its reverse (3123231551), we get a palindrome (4674554764).

The spelling of 1551323213 in words is "one billion, five hundred fifty-one million, three hundred twenty-three thousand, two hundred thirteen".