139781247 has 8 divisors (see below), whose sum is σ = 192801840. Its totient is φ = 89974080.

The previous prime is 139781231. The next prime is 139781303. The reversal of 139781247 is 742187931.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 139781247 - 2⁴ = 139781231 is a prime.

It is a Smith number, since the sum of its digits (42) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a junction number, because it is equal to n+sod(n) for n = 139781199 and 139781208.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (139741247) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 803254 + ... + 803427.

It is an arithmetic number, because the mean of its divisors is an integer number (24100230).

Almost surely, 2^139781247 is an apocalyptic number.

139781247 is a deficient number, since it is larger than the sum of its proper divisors (53020593).

139781247 is a wasteful number, since it uses less digits than its factorization.

139781247 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1606713.

The product of its digits is 84672, while the sum is 42.

The square root of 139781247 is about 11822.9119509535. The cubic root of 139781247 is about 518.9788230934.

It can be divided in two parts, 13978 and 1247, that added together give a triangular number (15225 = T₁₇₄).

The spelling of 139781247 in words is "one hundred thirty-nine million, seven hundred eighty-one thousand, two hundred forty-seven".