42664261 has 2 divisors, whose sum is σ = 42664262. Its totient is φ = 42664260.

The previous prime is 42664229. The next prime is 42664267. The reversal of 42664261 is 16246624.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 31708161 + 10956100 = 5631^2 + 3310^2 .

It is a cyclic number.

It is not a de Polignac number, because 42664261 - 2⁵ = 42664229 is a prime.

It is a super-2 number, since 2×42664261² = 3640478333352242, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (42664267) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21332130 + 21332131.

It is an arithmetic number, because the mean of its divisors is an integer number (21332131).

Almost surely, 2^42664261 is an apocalyptic number.

It is an amenable number.

42664261 is a deficient number, since it is larger than the sum of its proper divisors (1).

42664261 is an equidigital number, since it uses as much as digits as its factorization.

42664261 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 13824, while the sum is 31.

The square root of 42664261 is about 6531.7884993316. The cubic root of 42664261 is about 349.4256184479.

The spelling of 42664261 in words is "forty-two million, six hundred sixty-four thousand, two hundred sixty-one".