1242125569 has 4 divisors (see below), whose sum is σ = 1242222660. Its totient is φ = 1242028480.

The previous prime is 1242125567. The next prime is 1242125581. The reversal of 1242125569 is 9655212421.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 469285569 + 772840000 = 21663^2 + 27800^2 .

It is a cyclic number.

It is not a de Polignac number, because 1242125569 - 2¹ = 1242125567 is a prime.

It is a super-2 number, since 2×1242125569² = 3085751858327147522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1242125567) 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, 25804 + ... + 56125.

It is an arithmetic number, because the mean of its divisors is an integer number (310555665).

Almost surely, 2^1242125569 is an apocalyptic number.

It is an amenable number.

1242125569 is a deficient number, since it is larger than the sum of its proper divisors (97091).

1242125569 is an equidigital number, since it uses as much as digits as its factorization.

1242125569 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 97090.

The product of its digits is 43200, while the sum is 37.

The square root of 1242125569 is about 35243.8018522406. The cubic root of 1242125569 is about 1074.9505855058.

The spelling of 1242125569 in words is "one billion, two hundred forty-two million, one hundred twenty-five thousand, five hundred sixty-nine".