124720861 has 2 divisors, whose sum is σ = 124720862. Its totient is φ = 124720860.

The previous prime is 124720859. The next prime is 124720873. The reversal of 124720861 is 168027421.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 103652761 + 21068100 = 10181^2 + 4590^2 .

It is a cyclic number.

It is not a de Polignac number, because 124720861 - 2¹ = 124720859 is a prime.

Together with 124720859, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (124720361) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 62360430 + 62360431.

It is an arithmetic number, because the mean of its divisors is an integer number (62360431).

Almost surely, 2^124720861 is an apocalyptic number.

It is an amenable number.

124720861 is a deficient number, since it is larger than the sum of its proper divisors (1).

124720861 is an equidigital number, since it uses as much as digits as its factorization.

124720861 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 5376, while the sum is 31.

The square root of 124720861 is about 11167.8494348733. The cubic root of 124720861 is about 499.6275372786.

The spelling of 124720861 in words is "one hundred twenty-four million, seven hundred twenty thousand, eight hundred sixty-one".