125040043021 has 4 divisors (see below), whose sum is σ = 125084879100. Its totient is φ = 124995206944.

The previous prime is 125040043019. The next prime is 125040043049. The reversal of 125040043021 is 120340040521.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 104206296100 + 20833746921 = 322810^2 + 144339^2 .

It is a cyclic number.

It is not a de Polignac number, because 125040043021 - 2¹ = 125040043019 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 125040042983 and 125040043001.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (125040047021) 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, 22413856 + ... + 22419433.

It is an arithmetic number, because the mean of its divisors is an integer number (31271219775).

Almost surely, 2^125040043021 is an apocalyptic number.

It is an amenable number.

125040043021 is a deficient number, since it is larger than the sum of its proper divisors (44836079).

125040043021 is an equidigital number, since it uses as much as digits as its factorization.

125040043021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 44836078.

The product of its (nonzero) digits is 960, while the sum is 22.

Adding to 125040043021 its reverse (120340040521), we get a palindrome (245380083542).

The spelling of 125040043021 in words is "one hundred twenty-five billion, forty million, forty-three thousand, twenty-one".