205351421 has 16 divisors (see below), whose sum is σ = 226784448. Its totient is φ = 184396800.

The previous prime is 205351417. The next prime is 205351423. The reversal of 205351421 is 124153502.

It is a cyclic number.

It is not a de Polignac number, because 205351421 - 2² = 205351417 is a prime.

It is a super-2 number, since 2×205351421² = 84338412213438482, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (205351423) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 417986 + ... + 418476.

It is an arithmetic number, because the mean of its divisors is an integer number (14174028).

Almost surely, 2^205351421 is an apocalyptic number.

It is an amenable number.

205351421 is a deficient number, since it is larger than the sum of its proper divisors (21433027).

205351421 is a wasteful number, since it uses less digits than its factorization.

205351421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 892.

The product of its (nonzero) digits is 1200, while the sum is 23.

The square root of 205351421 is about 14330.0879620468. The cubic root of 205351421 is about 589.9735897400.

The spelling of 205351421 in words is "two hundred five million, three hundred fifty-one thousand, four hundred twenty-one".