1138657493 has 2 divisors, whose sum is σ = 1138657494. Its totient is φ = 1138657492.

The previous prime is 1138657463. The next prime is 1138657561. The reversal of 1138657493 is 3947568311.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1112422609 + 26234884 = 33353^2 + 5122^2 .

It is a cyclic number.

It is not a de Polignac number, because 1138657493 - 2²² = 1134463189 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1138657463) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 569328746 + 569328747.

It is an arithmetic number, because the mean of its divisors is an integer number (569328747).

Almost surely, 2^1138657493 is an apocalyptic number.

It is an amenable number.

1138657493 is a deficient number, since it is larger than the sum of its proper divisors (1).

1138657493 is an equidigital number, since it uses as much as digits as its factorization.

1138657493 is an evil number, because the sum of its binary digits is even.

The product of its digits is 544320, while the sum is 47.

The square root of 1138657493 is about 33743.9993628497. Note that the first 3 decimals coincide. The cubic root of 1138657493 is about 1044.2336950482.

The spelling of 1138657493 in words is "one billion, one hundred thirty-eight million, six hundred fifty-seven thousand, four hundred ninety-three".