67720291 has 4 divisors (see below), whose sum is σ = 67742784. Its totient is φ = 67697800.

The previous prime is 67720243. The next prime is 67720321. The reversal of 67720291 is 19202776.

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

It is a cyclic number.

It is not a de Polignac number, because 67720291 - 2¹¹ = 67718243 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (67720391) 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, 5875 + ... + 13036.

It is an arithmetic number, because the mean of its divisors is an integer number (16935696).

Almost surely, 2^67720291 is an apocalyptic number.

67720291 is a deficient number, since it is larger than the sum of its proper divisors (22493).

67720291 is a wasteful number, since it uses less digits than its factorization.

67720291 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22492.

The product of its (nonzero) digits is 10584, while the sum is 34.

The square root of 67720291 is about 8229.2339254635. The cubic root of 67720291 is about 407.6050961568.

The spelling of 67720291 in words is "sixty-seven million, seven hundred twenty thousand, two hundred ninety-one".