66729437 has 4 divisors (see below), whose sum is σ = 70654716. Its totient is φ = 62804160.

The previous prime is 66729433. The next prime is 66729469. The reversal of 66729437 is 73492766.

It is a happy number.

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 62315236 + 4414201 = 7894^2 + 2101^2 .

It is a cyclic number.

It is not a de Polignac number, because 66729437 - 2² = 66729433 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 (66729431) 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, 1962614 + ... + 1962647.

It is an arithmetic number, because the mean of its divisors is an integer number (17663679).

Almost surely, 2^66729437 is an apocalyptic number.

It is an amenable number.

66729437 is a deficient number, since it is larger than the sum of its proper divisors (3925279).

66729437 is a wasteful number, since it uses less digits than its factorization.

66729437 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3925278.

The product of its digits is 381024, while the sum is 44.

The square root of 66729437 is about 8168.8087870876. The cubic root of 66729437 is about 405.6073537337.

The spelling of 66729437 in words is "sixty-six million, seven hundred twenty-nine thousand, four hundred thirty-seven".