139218623 has 2 divisors, whose sum is σ = 139218624. Its totient is φ = 139218622.

The previous prime is 139218617. The next prime is 139218637. The reversal of 139218623 is 326812931.

It is a weak prime.

It is an emirp because it is prime and its reverse (326812931) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 139218623 - 2⁸ = 139218367 is a prime.

It is a super-2 number, since 2×139218623² = 38763649980032258, which contains 22 as substring.

It is equal to p_7870418 and since 139218623 and 7870418 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 (139218223) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 69609311 + 69609312.

It is an arithmetic number, because the mean of its divisors is an integer number (69609312).

Almost surely, 2^139218623 is an apocalyptic number.

139218623 is a deficient number, since it is larger than the sum of its proper divisors (1).

139218623 is an equidigital number, since it uses as much as digits as its factorization.

139218623 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 15552, while the sum is 35.

The square root of 139218623 is about 11799.0941601464. The cubic root of 139218623 is about 518.2815846528.

The spelling of 139218623 in words is "one hundred thirty-nine million, two hundred eighteen thousand, six hundred twenty-three".