340242421 has 2 divisors, whose sum is σ = 340242422. Its totient is φ = 340242420.

The previous prime is 340242401. The next prime is 340242431. The reversal of 340242421 is 124242043.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 204776100 + 135466321 = 14310^2 + 11639^2 .

It is a cyclic number.

It is not a de Polignac number, because 340242421 - 2²³ = 331853813 is a prime.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 340242392 and 340242401.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (340242401) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 170121210 + 170121211.

It is an arithmetic number, because the mean of its divisors is an integer number (170121211).

Almost surely, 2^340242421 is an apocalyptic number.

It is an amenable number.

340242421 is a deficient number, since it is larger than the sum of its proper divisors (1).

340242421 is an equidigital number, since it uses as much as digits as its factorization.

340242421 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1536, while the sum is 22.

The square root of 340242421 is about 18445.6613055754. The cubic root of 340242421 is about 698.1190461779.

Adding to 340242421 its reverse (124242043), we get a palindrome (464484464).

The spelling of 340242421 in words is "three hundred forty million, two hundred forty-two thousand, four hundred twenty-one".