66534261 has 4 divisors (see below), whose sum is σ = 88712352. Its totient is φ = 44356172.

The previous prime is 66534253. The next prime is 66534269. The reversal of 66534261 is 16243566.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is an interprime number because it is at equal distance from previous prime (66534253) and next prime (66534269).

It is a cyclic number.

It is not a de Polignac number, because 66534261 - 2³ = 66534253 is a prime.

It is a super-2 number, since 2×66534261² = 8853615773632242, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66534269) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 11089041 + ... + 11089046.

It is an arithmetic number, because the mean of its divisors is an integer number (22178088).

Almost surely, 2^66534261 is an apocalyptic number.

It is an amenable number.

66534261 is a deficient number, since it is larger than the sum of its proper divisors (22178091).

66534261 is a wasteful number, since it uses less digits than its factorization.

66534261 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22178090.

The product of its digits is 25920, while the sum is 33.

The square root of 66534261 is about 8156.8536213420. The cubic root of 66534261 is about 405.2115157908.

It can be divided in two parts, 66534 and 261, that added together give a triangular number (66795 = T₃₆₅).

The spelling of 66534261 in words is "sixty-six million, five hundred thirty-four thousand, two hundred sixty-one".