431520421 has 2 divisors, whose sum is σ = 431520422. Its totient is φ = 431520420.

The previous prime is 431520409. The next prime is 431520431. The reversal of 431520421 is 124025134.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 226171521 + 205348900 = 15039^2 + 14330^2 .

It is a cyclic number.

It is not a de Polignac number, because 431520421 - 2⁹ = 431519909 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 431520392 and 431520401.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (431520431) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 215760210 + 215760211.

It is an arithmetic number, because the mean of its divisors is an integer number (215760211).

Almost surely, 2^431520421 is an apocalyptic number.

It is an amenable number.

431520421 is a deficient number, since it is larger than the sum of its proper divisors (1).

431520421 is an equidigital number, since it uses as much as digits as its factorization.

431520421 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 960, while the sum is 22.

The square root of 431520421 is about 20773.0696094727. The cubic root of 431520421 is about 755.6727894701.

Adding to 431520421 its reverse (124025134), we get a palindrome (555545555).

The spelling of 431520421 in words is "four hundred thirty-one million, five hundred twenty thousand, four hundred twenty-one".