67905421 has 2 divisors, whose sum is σ = 67905422. Its totient is φ = 67905420.

The previous prime is 67905419. The next prime is 67905451. The reversal of 67905421 is 12450976.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 46049796 + 21855625 = 6786^2 + 4675^2 .

It is a cyclic number.

It is not a de Polignac number, because 67905421 - 2¹ = 67905419 is a prime.

It is a super-2 number, since 2×67905421² = 9222292402374482, which contains 22 as substring.

Together with 67905419, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (67905451) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33952710 + 33952711.

It is an arithmetic number, because the mean of its divisors is an integer number (33952711).

Almost surely, 2^67905421 is an apocalyptic number.

It is an amenable number.

67905421 is a deficient number, since it is larger than the sum of its proper divisors (1).

67905421 is an equidigital number, since it uses as much as digits as its factorization.

67905421 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 15120, while the sum is 34.

The square root of 67905421 is about 8240.4745615771. The cubic root of 67905421 is about 407.9761876561.

The spelling of 67905421 in words is "sixty-seven million, nine hundred five thousand, four hundred twenty-one".