125633989 has 4 divisors (see below), whose sum is σ = 135298156. Its totient is φ = 115969824.

The previous prime is 125633987. The next prime is 125633999. The reversal of 125633989 is 989336521.

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: 989336521 = 13121 ⋅75401.

It can be written as a sum of positive squares in 2 ways, for example, as 84456100 + 41177889 = 9190^2 + 6417^2 .

It is a cyclic number.

It is not a de Polignac number, because 125633989 - 2¹ = 125633987 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (125633983) 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, 4832064 + ... + 4832089.

It is an arithmetic number, because the mean of its divisors is an integer number (33824539).

Almost surely, 2^125633989 is an apocalyptic number.

It is an amenable number.

125633989 is a deficient number, since it is larger than the sum of its proper divisors (9664167).

125633989 is an equidigital number, since it uses as much as digits as its factorization.

125633989 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9664166.

The product of its digits is 349920, while the sum is 46.

The square root of 125633989 is about 11208.6568776103. The cubic root of 125633989 is about 500.8438935527.

It can be divided in two parts, 1256 and 33989, that added together give a triangular number (35245 = T₂₆₅).

The spelling of 125633989 in words is "one hundred twenty-five million, six hundred thirty-three thousand, nine hundred eighty-nine".