138782551 has 2 divisors, whose sum is σ = 138782552. Its totient is φ = 138782550.

The previous prime is 138782537. The next prime is 138782591. The reversal of 138782551 is 155287831.

138782551 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an a-pointer prime, because the next prime (138782591) can be obtained adding 138782551 to its sum of digits (40).

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 138782551 - 2¹⁵ = 138749783 is a prime.

It is equal to p_7847158 and since 138782551 and 7847158 have the same sum of digits, it is a Honaker prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (138782521) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 69391275 + 69391276.

It is an arithmetic number, because the mean of its divisors is an integer number (69391276).

Almost surely, 2^138782551 is an apocalyptic number.

138782551 is a deficient number, since it is larger than the sum of its proper divisors (1).

138782551 is an equidigital number, since it uses as much as digits as its factorization.

138782551 is an evil number, because the sum of its binary digits is even.

The product of its digits is 67200, while the sum is 40.

The square root of 138782551 is about 11780.6006213605. The cubic root of 138782551 is about 517.7398839629.

It can be divided in two parts, 1387 and 82551, that added together give a palindrome (83938).

The spelling of 138782551 in words is "one hundred thirty-eight million, seven hundred eighty-two thousand, five hundred fifty-one".