67616621 has 4 divisors (see below), whose sum is σ = 67712700. Its totient is φ = 67520544.

The previous prime is 67616587. The next prime is 67616623. The reversal of 67616621 is 12661676.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 6604900 + 61011721 = 2570^2 + 7811^2 .

It is a cyclic number.

It is not a de Polignac number, because 67616621 - 2⁶ = 67616557 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (67616623) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 46976 + ... + 48393.

It is an arithmetic number, because the mean of its divisors is an integer number (16928175).

Almost surely, 2^67616621 is an apocalyptic number.

It is an amenable number.

67616621 is a deficient number, since it is larger than the sum of its proper divisors (96079).

67616621 is an equidigital number, since it uses as much as digits as its factorization.

67616621 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 96078.

The product of its digits is 18144, while the sum is 35.

The square root of 67616621 is about 8222.9326277187. The cubic root of 67616621 is about 407.3969950551.

The spelling of 67616621 in words is "sixty-seven million, six hundred sixteen thousand, six hundred twenty-one".