61666403 has 2 divisors, whose sum is σ = 61666404. Its totient is φ = 61666402.

The previous prime is 61666393. The next prime is 61666417. The reversal of 61666403 is 30466616.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 61666403 - 2²² = 57472099 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 61666403.

It is not a weakly prime, because it can be changed into another prime (61666453) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 30833201 + 30833202.

It is an arithmetic number, because the mean of its divisors is an integer number (30833202).

Almost surely, 2^61666403 is an apocalyptic number.

61666403 is a deficient number, since it is larger than the sum of its proper divisors (1).

61666403 is an equidigital number, since it uses as much as digits as its factorization.

61666403 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 15552, while the sum is 32.

The square root of 61666403 is about 7852.7958715352. The cubic root of 61666403 is about 395.0780233631.

The spelling of 61666403 in words is "sixty-one million, six hundred sixty-six thousand, four hundred three".