1243025638 has 32 divisors (see below), whose sum is σ = 2014064640. Its totient is φ = 573505920.

The previous prime is 1243025633. The next prime is 1243025681. The reversal of 1243025638 is 8365203421.

It is a super-2 number, since 2×1243025638² = 3090225473450614088, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1243025633) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 396718 + ... + 399838.

It is an arithmetic number, because the mean of its divisors is an integer number (62939520).

Almost surely, 2^1243025638 is an apocalyptic number.

1243025638 is a deficient number, since it is larger than the sum of its proper divisors (771039002).

1243025638 is a wasteful number, since it uses less digits than its factorization.

1243025638 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3412.

The product of its (nonzero) digits is 34560, while the sum is 34.

The square root of 1243025638 is about 35256.5687213036. The cubic root of 1243025638 is about 1075.2101663725.

The spelling of 1243025638 in words is "one billion, two hundred forty-three million, twenty-five thousand, six hundred thirty-eight".