67701721 has 2 divisors, whose sum is σ = 67701722. Its totient is φ = 67701720.

The previous prime is 67701713. The next prime is 67701727. The reversal of 67701721 is 12710776.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 54597321 + 13104400 = 7389^2 + 3620^2 .

It is a cyclic number.

It is not a de Polignac number, because 67701721 - 2³ = 67701713 is a prime.

It is not a weakly prime, because it can be changed into another prime (67701727) 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, 33850860 + 33850861.

It is an arithmetic number, because the mean of its divisors is an integer number (33850861).

Almost surely, 2^67701721 is an apocalyptic number.

It is an amenable number.

67701721 is a deficient number, since it is larger than the sum of its proper divisors (1).

67701721 is an equidigital number, since it uses as much as digits as its factorization.

67701721 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 4116, while the sum is 31.

The square root of 67701721 is about 8228.1055535281. The cubic root of 67701721 is about 407.5678354457.

The spelling of 67701721 in words is "sixty-seven million, seven hundred one thousand, seven hundred twenty-one".