1251522165 has 16 divisors (see below), whose sum is σ = 2002932288. Its totient is φ = 667312896.

The previous prime is 1251522163. The next prime is 1251522179. The reversal of 1251522165 is 5612251521.

It is not a de Polignac number, because 1251522165 - 2¹ = 1251522163 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1251522163) 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, 74637 + ... + 89853.

It is an arithmetic number, because the mean of its divisors is an integer number (125183268).

Almost surely, 2^1251522165 is an apocalyptic number.

1251522165 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1251522165 is a deficient number, since it is larger than the sum of its proper divisors (751410123).

1251522165 is a wasteful number, since it uses less digits than its factorization.

1251522165 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20708.

The product of its digits is 6000, while the sum is 30.

The square root of 1251522165 is about 35376.8591737593. The cubic root of 1251522165 is about 1077.6544216605.

Adding to 1251522165 its reverse (5612251521), we get a palindrome (6863773686).

The spelling of 1251522165 in words is "one billion, two hundred fifty-one million, five hundred twenty-two thousand, one hundred sixty-five".