423409821 has 4 divisors (see below), whose sum is σ = 564546432. Its totient is φ = 282273212.

The previous prime is 423409801. The next prime is 423409841. The reversal of 423409821 is 128904324.

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 an interprime number because it is at equal distance from previous prime (423409801) and next prime (423409841).

It is a cyclic number.

It is not a de Polignac number, because 423409821 - 2²⁷ = 289192093 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (423409801) 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, 70568301 + ... + 70568306.

It is an arithmetic number, because the mean of its divisors is an integer number (141136608).

Almost surely, 2^423409821 is an apocalyptic number.

It is an amenable number.

423409821 is a deficient number, since it is larger than the sum of its proper divisors (141136611).

423409821 is a wasteful number, since it uses less digits than its factorization.

423409821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 141136610.

The product of its (nonzero) digits is 13824, while the sum is 33.

The square root of 423409821 is about 20576.9244786484. The cubic root of 423409821 is about 750.9084228020.

The spelling of 423409821 in words is "four hundred twenty-three million, four hundred nine thousand, eight hundred twenty-one".