1866620429 has 2 divisors, whose sum is σ = 1866620430. Its totient is φ = 1866620428.

The previous prime is 1866620423. The next prime is 1866620443. The reversal of 1866620429 is 9240266681.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1195292329 + 671328100 = 34573^2 + 25910^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1866620429 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1866620429.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1866620423) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 933310214 + 933310215.

It is an arithmetic number, because the mean of its divisors is an integer number (933310215).

Almost surely, 2^1866620429 is an apocalyptic number.

It is an amenable number.

1866620429 is a deficient number, since it is larger than the sum of its proper divisors (1).

1866620429 is an equidigital number, since it uses as much as digits as its factorization.

1866620429 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 248832, while the sum is 44.

The square root of 1866620429 is about 43204.4028890575. The cubic root of 1866620429 is about 1231.2663339017.

The spelling of 1866620429 in words is "one billion, eight hundred sixty-six million, six hundred twenty thousand, four hundred twenty-nine".