67720511 has 4 divisors (see below), whose sum is σ = 67753224. Its totient is φ = 67687800.

The previous prime is 67720507. The next prime is 67720531. The reversal of 67720511 is 11502776.

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 67720511 - 2² = 67720507 is a prime.

It is a super-2 number, since 2×67720511² = 9172135220202242, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (67720531) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 13025 + ... + 17466.

It is an arithmetic number, because the mean of its divisors is an integer number (16938306).

Almost surely, 2^67720511 is an apocalyptic number.

67720511 is a deficient number, since it is larger than the sum of its proper divisors (32713).

67720511 is a wasteful number, since it uses less digits than its factorization.

67720511 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 32712.

The product of its (nonzero) digits is 2940, while the sum is 29.

The square root of 67720511 is about 8229.2472924320. The cubic root of 67720511 is about 407.6055375461.

The spelling of 67720511 in words is "sixty-seven million, seven hundred twenty thousand, five hundred eleven".