421901 has 4 divisors (see below), whose sum is σ = 425952. Its totient is φ = 417852.

The previous prime is 421891. The next prime is 421907. The reversal of 421901 is 109124.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-421901 is a prime.

It is an Ulam number.

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 421901.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (421907) 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, 1865 + ... + 2078.

It is an arithmetic number, because the mean of its divisors is an integer number (106488).

2⁴²¹⁹⁰¹ is an apocalyptic number.

It is an amenable number.

421901 is a deficient number, since it is larger than the sum of its proper divisors (4051).

421901 is a wasteful number, since it uses less digits than its factorization.

421901 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4050.

The product of its (nonzero) digits is 72, while the sum is 17.

The square root of 421901 is about 649.5390673393. The cubic root of 421901 is about 75.0015407091.

The spelling of 421901 in words is "four hundred twenty-one thousand, nine hundred one".