1621432201 has 8 divisors (see below), whose sum is σ = 1630280520. Its totient is φ = 1612605312.

The previous prime is 1621432177. The next prime is 1621432213. The reversal of 1621432201 is 1022341261.

It can be written as a sum of positive squares in 4 ways, for example, as 80084601 + 1541347600 = 8949^2 + 39260^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1621432201 - 2²⁵ = 1587877769 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1621432271) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 159981 + ... + 169813.

It is an arithmetic number, because the mean of its divisors is an integer number (203785065).

Almost surely, 2^1621432201 is an apocalyptic number.

It is an amenable number.

1621432201 is a deficient number, since it is larger than the sum of its proper divisors (8848319).

1621432201 is an equidigital number, since it uses as much as digits as its factorization.

1621432201 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10715.

The product of its (nonzero) digits is 576, while the sum is 22.

The square root of 1621432201 is about 40267.0113244080. The cubic root of 1621432201 is about 1174.8062939471.

Adding to 1621432201 its reverse (1022341261), we get a palindrome (2643773462).

The spelling of 1621432201 in words is "one billion, six hundred twenty-one million, four hundred thirty-two thousand, two hundred one".