423973981 has 8 divisors (see below), whose sum is σ = 433964160. Its totient is φ = 414024288.

The previous prime is 423973943. The next prime is 423974039. The reversal of 423973981 is 189379324.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 423973981 - 2²⁷ = 289756253 is a prime.

It is a super-2 number, since 2×423973981² = 359507873129976722, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (423973181) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 11610 + ... + 31348.

It is an arithmetic number, because the mean of its divisors is an integer number (54245520).

Almost surely, 2^423973981 is an apocalyptic number.

It is an amenable number.

423973981 is a deficient number, since it is larger than the sum of its proper divisors (9990179).

423973981 is a wasteful number, since it uses less digits than its factorization.

423973981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20243.

The product of its digits is 326592, while the sum is 46.

The square root of 423973981 is about 20590.6284751097. The cubic root of 423973981 is about 751.2417834231.

The spelling of 423973981 in words is "four hundred twenty-three million, nine hundred seventy-three thousand, nine hundred eighty-one".