125001691 has 4 divisors (see below), whose sum is σ = 125025912. Its totient is φ = 124977472.

The previous prime is 125001689. The next prime is 125001713. The reversal of 125001691 is 196100521.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 196100521 = 12277 ⋅15973.

It is a cyclic number.

It is not a de Polignac number, because 125001691 - 2¹ = 125001689 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (125001631) 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, 925 + ... + 15838.

It is an arithmetic number, because the mean of its divisors is an integer number (31256478).

Almost surely, 2^125001691 is an apocalyptic number.

125001691 is a deficient number, since it is larger than the sum of its proper divisors (24221).

125001691 is an equidigital number, since it uses as much as digits as its factorization.

125001691 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24220.

The product of its (nonzero) digits is 540, while the sum is 25.

The square root of 125001691 is about 11180.4155110622. The cubic root of 125001691 is about 500.0022546565.

The spelling of 125001691 in words is "one hundred twenty-five million, one thousand, six hundred ninety-one".