67400369921 has 2 divisors, whose sum is σ = 67400369922. Its totient is φ = 67400369920.

The previous prime is 67400369887. The next prime is 67400370041. The reversal of 67400369921 is 12996300476.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 43948510321 + 23451859600 = 209639^2 + 153140^2 .

It is a cyclic number.

It is not a de Polignac number, because 67400369921 - 2⁶ = 67400369857 is a prime.

It is not a weakly prime, because it can be changed into another prime (67400369521) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33700184960 + 33700184961.

It is an arithmetic number, because the mean of its divisors is an integer number (33700184961).

Almost surely, 2^67400369921 is an apocalyptic number.

It is an amenable number.

67400369921 is a deficient number, since it is larger than the sum of its proper divisors (1).

67400369921 is an equidigital number, since it uses as much as digits as its factorization.

67400369921 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 489888, while the sum is 47.

The spelling of 67400369921 in words is "sixty-seven billion, four hundred million, three hundred sixty-nine thousand, nine hundred twenty-one".