421402001 has 4 divisors (see below), whose sum is σ = 446190372. Its totient is φ = 396613632.

The previous prime is 421401989. The next prime is 421402027. The reversal of 421402001 is 100204124.

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 209670400 + 211731601 = 14480^2 + 14551^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-421402001 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (421402301) 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 3 ways as a sum of consecutive naturals, for example, 12394160 + ... + 12394193.

It is an arithmetic number, because the mean of its divisors is an integer number (111547593).

Almost surely, 2^421402001 is an apocalyptic number.

It is an amenable number.

421402001 is a deficient number, since it is larger than the sum of its proper divisors (24788371).

421402001 is a wasteful number, since it uses less digits than its factorization.

421402001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 24788370.

The product of its (nonzero) digits is 64, while the sum is 14.

The square root of 421402001 is about 20528.0783562417. The cubic root of 421402001 is about 749.7195994768.

Adding to 421402001 its reverse (100204124), we get a palindrome (521606125).

The spelling of 421402001 in words is "four hundred twenty-one million, four hundred two thousand, one".