1620001 has 2 divisors, whose sum is σ = 1620002. Its totient is φ = 1620000.

The previous prime is 1619987. The next prime is 1620013. The reversal of 1620001 is 1000261.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1288225 + 331776 = 1135^2 + 576^2 .

It is a cyclic number.

It is not a de Polignac number, because 1620001 - 2¹³ = 1611809 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1620001.

It is not a weakly prime, because it can be changed into another prime (1620041) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 810000 + 810001.

It is an arithmetic number, because the mean of its divisors is an integer number (810001).

2^1620001 is an apocalyptic number.

It is an amenable number.

1620001 is a deficient number, since it is larger than the sum of its proper divisors (1).

1620001 is an equidigital number, since it uses as much as digits as its factorization.

1620001 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 12, while the sum is 10.

The square root of 1620001 is about 1272.7925989728. The cubic root of 1620001 is about 117.4460534009.

Adding to 1620001 its reverse (1000261), we get a palindrome (2620262).

The spelling of 1620001 in words is "one million, six hundred twenty thousand, one".