1641632401 has 4 divisors (see below), whose sum is σ = 1641758692. Its totient is φ = 1641506112.

The previous prime is 1641632381. The next prime is 1641632411. The reversal of 1641632401 is 1042361461.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 829382401 + 812250000 = 28799^2 + 28500^2 .

It is a cyclic number.

It is not a de Polignac number, because 1641632401 - 2⁷ = 1641632273 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1641632401.

It is not an unprimeable number, because it can be changed into a prime (1641632411) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 41076 + ... + 70501.

It is an arithmetic number, because the mean of its divisors is an integer number (410439673).

Almost surely, 2^1641632401 is an apocalyptic number.

It is an amenable number.

1641632401 is a deficient number, since it is larger than the sum of its proper divisors (126291).

1641632401 is a wasteful number, since it uses less digits than its factorization.

1641632401 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 126290.

The product of its (nonzero) digits is 3456, while the sum is 28.

The square root of 1641632401 is about 40517.0630845820. The cubic root of 1641632401 is about 1179.6648480802.

Adding to 1641632401 its reverse (1042361461), we get a palindrome (2683993862).

The spelling of 1641632401 in words is "one billion, six hundred forty-one million, six hundred thirty-two thousand, four hundred one".