125815801 has 4 divisors (see below), whose sum is σ = 127061604. Its totient is φ = 124570000.

The previous prime is 125815771. The next prime is 125815817. The reversal of 125815801 is 108518521.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 108518521 = 37 ⋅2932933.

It can be written as a sum of positive squares in 2 ways, for example, as 84548025 + 41267776 = 9195^2 + 6424^2 .

It is a cyclic number.

It is not a de Polignac number, because 125815801 - 2⁷ = 125815673 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (125815841) 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, 622750 + ... + 622951.

It is an arithmetic number, because the mean of its divisors is an integer number (31765401).

Almost surely, 2^125815801 is an apocalyptic number.

It is an amenable number.

125815801 is a deficient number, since it is larger than the sum of its proper divisors (1245803).

125815801 is a wasteful number, since it uses less digits than its factorization.

125815801 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1245802.

The product of its (nonzero) digits is 3200, while the sum is 31.

The square root of 125815801 is about 11216.7642838744. The cubic root of 125815801 is about 501.0853768759.

The spelling of 125815801 in words is "one hundred twenty-five million, eight hundred fifteen thousand, eight hundred one".