1551325121 has 4 divisors (see below), whose sum is σ = 1554908292. Its totient is φ = 1547741952.

The previous prime is 1551325093. The next prime is 1551325163. The reversal of 1551325121 is 1215231551.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 769507600 + 781817521 = 27740^2 + 27961^2 .

It is a cyclic number.

It is not a de Polignac number, because 1551325121 - 2⁶ = 1551325057 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1551322121) 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, 1790936 + ... + 1791801.

It is an arithmetic number, because the mean of its divisors is an integer number (388727073).

Almost surely, 2^1551325121 is an apocalyptic number.

It is an amenable number.

1551325121 is a deficient number, since it is larger than the sum of its proper divisors (3583171).

1551325121 is an equidigital number, since it uses as much as digits as its factorization.

1551325121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3583170.

The product of its digits is 1500, while the sum is 26.

The square root of 1551325121 is about 39386.8648282648. The cubic root of 1551325121 is about 1157.6242301593.

Adding to 1551325121 its reverse (1215231551), we get a palindrome (2766556672).

The spelling of 1551325121 in words is "one billion, five hundred fifty-one million, three hundred twenty-five thousand, one hundred twenty-one".