1601602021 has 2 divisors, whose sum is σ = 1601602022. Its totient is φ = 1601602020.

The previous prime is 1601602003. The next prime is 1601602027. The reversal of 1601602021 is 1202061061.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1268356996 + 333245025 = 35614^2 + 18255^2 .

It is an emirp because it is prime and its reverse (1202061061) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1601602021 - 2¹⁵ = 1601569253 is a prime.

It is a super-3 number, since 3×1601602021³ (a number of 29 digits) contains 333 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 1601602021.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1601602027) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 800801010 + 800801011.

It is an arithmetic number, because the mean of its divisors is an integer number (800801011).

Almost surely, 2^1601602021 is an apocalyptic number.

It is an amenable number.

1601602021 is a deficient number, since it is larger than the sum of its proper divisors (1).

1601602021 is an equidigital number, since it uses as much as digits as its factorization.

1601602021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 144, while the sum is 19.

The square root of 1601602021 is about 40020.0202523687. The cubic root of 1601602021 is about 1169.9973265578.

Adding to 1601602021 its reverse (1202061061), we get a palindrome (2803663082).

The spelling of 1601602021 in words is "one billion, six hundred one million, six hundred two thousand, twenty-one".