125138747491 has 2 divisors, whose sum is σ = 125138747492. Its totient is φ = 125138747490.

The previous prime is 125138747471. The next prime is 125138747519. The reversal of 125138747491 is 194747831521.

It is a weak prime.

It is an emirp because it is prime and its reverse (194747831521) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 125138747491 - 2²³ = 125130358883 is a prime.

It is a super-2 number, since 2×125138747491² (a number of 23 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (125138747401) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 62569373745 + 62569373746.

It is an arithmetic number, because the mean of its divisors is an integer number (62569373746).

Almost surely, 2^125138747491 is an apocalyptic number.

125138747491 is a deficient number, since it is larger than the sum of its proper divisors (1).

125138747491 is an equidigital number, since it uses as much as digits as its factorization.

125138747491 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1693440, while the sum is 52.

The spelling of 125138747491 in words is "one hundred twenty-five billion, one hundred thirty-eight million, seven hundred forty-seven thousand, four hundred ninety-one".