655421421 has 8 divisors (see below), whose sum is σ = 882548064. Its totient is φ = 432621200.

The previous prime is 655421387. The next prime is 655421423. The reversal of 655421421 is 124124556.

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 655421421 - 2²⁷ = 521203693 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (655421423) 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, 1081251 + ... + 1081856.

It is an arithmetic number, because the mean of its divisors is an integer number (110318508).

Almost surely, 2^655421421 is an apocalyptic number.

It is an amenable number.

655421421 is a deficient number, since it is larger than the sum of its proper divisors (227126643).

655421421 is a wasteful number, since it uses less digits than its factorization.

655421421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2163211.

The product of its digits is 9600, while the sum is 30.

The square root of 655421421 is about 25601.1996008000. The cubic root of 655421421 is about 868.6407722447.

Adding to 655421421 its reverse (124124556), we get a palindrome (779545977).

The spelling of 655421421 in words is "six hundred fifty-five million, four hundred twenty-one thousand, four hundred twenty-one".