1252638890 has 16 divisors (see below), whose sum is σ = 2256190632. Its totient is φ = 500735424.

The previous prime is 1252638889. The next prime is 1252638967. The reversal of 1252638890 is 988362521.

It can be written as a sum of positive squares in 4 ways, for example, as 633176569 + 619462321 = 25163^2 + 24889^2 .

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 23249 + ... + 55188.

Almost surely, 2^1252638890 is an apocalyptic number.

1252638890 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1252638890 is a deficient number, since it is larger than the sum of its proper divisors (1003551742).

1252638890 is a wasteful number, since it uses less digits than its factorization.

1252638890 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 80041.

The product of its (nonzero) digits is 207360, while the sum is 44.

The square root of 1252638890 is about 35392.6389239345. The cubic root of 1252638890 is about 1077.9748543580.

The spelling of 1252638890 in words is "one billion, two hundred fifty-two million, six hundred thirty-eight thousand, eight hundred ninety".