1641623 has 2 divisors, whose sum is σ = 1641624. Its totient is φ = 1641622.

The previous prime is 1641617. The next prime is 1641631. The reversal of 1641623 is 3261461.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1641623 - 2⁶ = 1641559 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1641613) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 820811 + 820812.

It is an arithmetic number, because the mean of its divisors is an integer number (820812).

2^1641623 is an apocalyptic number.

1641623 is a deficient number, since it is larger than the sum of its proper divisors (1).

1641623 is an equidigital number, since it uses as much as digits as its factorization.

1641623 is an evil number, because the sum of its binary digits is even.

The product of its digits is 864, while the sum is 23.

The square root of 1641623 is about 1281.2583658263. The cubic root of 1641623 is about 117.9662596246.

The spelling of 1641623 in words is "one million, six hundred forty-one thousand, six hundred twenty-three".