125652165509 has 4 divisors (see below), whose sum is σ = 135317716716. Its totient is φ = 115986614304.

The previous prime is 125652165461. The next prime is 125652165517. The reversal of 125652165509 is 905561256521.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 905561256521 = 251 ⋅3607813771.

It can be written as a sum of positive squares in 2 ways, for example, as 23314236100 + 102337929409 = 152690^2 + 319903^2 .

It is a cyclic number.

It is not a de Polignac number, because 125652165509 - 2⁸ = 125652165253 is a prime.

It is a super-2 number, since 2×125652165509² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (125652165599) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4832775584 + ... + 4832775609.

It is an arithmetic number, because the mean of its divisors is an integer number (33829429179).

Almost surely, 2^125652165509 is an apocalyptic number.

It is an amenable number.

125652165509 is a deficient number, since it is larger than the sum of its proper divisors (9665551207).

125652165509 is an equidigital number, since it uses as much as digits as its factorization.

125652165509 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9665551206.

The product of its (nonzero) digits is 810000, while the sum is 47.

The spelling of 125652165509 in words is "one hundred twenty-five billion, six hundred fifty-two million, one hundred sixty-five thousand, five hundred nine".