123640547 has 2 divisors, whose sum is σ = 123640548. Its totient is φ = 123640546.

The previous prime is 123640519. The next prime is 123640591. The reversal of 123640547 is 745046321.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 123640547 - 2¹² = 123636451 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (123640147) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 61820273 + 61820274.

It is an arithmetic number, because the mean of its divisors is an integer number (61820274).

Almost surely, 2^123640547 is an apocalyptic number.

123640547 is a deficient number, since it is larger than the sum of its proper divisors (1).

123640547 is an equidigital number, since it uses as much as digits as its factorization.

123640547 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 20160, while the sum is 32.

The square root of 123640547 is about 11119.3770958629. The cubic root of 123640547 is about 498.1807849408.

Adding to 123640547 its reverse (745046321), we get a palindrome (868686868).

The spelling of 123640547 in words is "one hundred twenty-three million, six hundred forty thousand, five hundred forty-seven".