247135639 has 2 divisors, whose sum is σ = 247135640. Its totient is φ = 247135638.

The previous prime is 247135607. The next prime is 247135657. The reversal of 247135639 is 936531742.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 247135639 - 2⁵ = 247135607 is a prime.

It is a super-2 number, since 2×247135639² = 122152048127876642, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (247135139) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 123567819 + 123567820.

It is an arithmetic number, because the mean of its divisors is an integer number (123567820).

Almost surely, 2^247135639 is an apocalyptic number.

247135639 is a deficient number, since it is larger than the sum of its proper divisors (1).

247135639 is an equidigital number, since it uses as much as digits as its factorization.

247135639 is an evil number, because the sum of its binary digits is even.

The product of its digits is 136080, while the sum is 40.

The square root of 247135639 is about 15720.5483046871. The cubic root of 247135639 is about 627.5453649948.

The spelling of 247135639 in words is "two hundred forty-seven million, one hundred thirty-five thousand, six hundred thirty-nine".