66430742261 has 16 divisors (see below), whose sum is σ = 72324228144. Its totient is φ = 60649979904.

The previous prime is 66430742227. The next prime is 66430742267. The reversal of 66430742261 is 16224703466.

It can be written as a sum of positive squares in 8 ways, for example, as 2315438161 + 64115304100 = 48119^2 + 253210^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-66430742261 is a prime.

It is a super-2 number, since 2×66430742261² (a number of 22 digits) 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 (66430742267) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2073581 + ... + 2105373.

It is an arithmetic number, because the mean of its divisors is an integer number (4520264259).

Almost surely, 2^66430742261 is an apocalyptic number.

It is an amenable number.

66430742261 is a deficient number, since it is larger than the sum of its proper divisors (5893485883).

66430742261 is a wasteful number, since it uses less digits than its factorization.

66430742261 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 33560.

The product of its (nonzero) digits is 290304, while the sum is 41.

The spelling of 66430742261 in words is "sixty-six billion, four hundred thirty million, seven hundred forty-two thousand, two hundred sixty-one".