15642001 has 6 divisors (see below), whose sum is σ = 16352210. Its totient is φ = 14961408.

The previous prime is 15641987. The next prime is 15642013. The reversal of 15642001 is 10024651.

It can be written as a sum of positive squares in only one way, i.e., 13542400 + 2099601 = 3680^2 + 1449^2 .

It is not a de Polignac number, because 15642001 - 2⁹ = 15641489 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 15642001.

It is not an unprimeable number, because it can be changed into a prime (15642031) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 14256 + ... + 15313.

Almost surely, 2^15642001 is an apocalyptic number.

It is an amenable number.

15642001 is a deficient number, since it is larger than the sum of its proper divisors (710209).

15642001 is an equidigital number, since it uses as much as digits as its factorization.

15642001 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 29615 (or 29592 counting only the distinct ones).

The product of its (nonzero) digits is 240, while the sum is 19.

The square root of 15642001 is about 3954.9969658648. The cubic root of 15642001 is about 250.0906391342.

Adding to 15642001 its reverse (10024651), we get a palindrome (25666652).

The spelling of 15642001 in words is "fifteen million, six hundred forty-two thousand, one".