66748531 has 2 divisors, whose sum is σ = 66748532. Its totient is φ = 66748530.

The previous prime is 66748489. The next prime is 66748541. The reversal of 66748531 is 13584766.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 66748531 - 2¹⁹ = 66224243 is a prime.

It is a super-2 number, since 2×66748531² = 8910732781315922, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (66748541) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33374265 + 33374266.

It is an arithmetic number, because the mean of its divisors is an integer number (33374266).

Almost surely, 2^66748531 is an apocalyptic number.

66748531 is a deficient number, since it is larger than the sum of its proper divisors (1).

66748531 is an equidigital number, since it uses as much as digits as its factorization.

66748531 is an evil number, because the sum of its binary digits is even.

The product of its digits is 120960, while the sum is 40.

The square root of 66748531 is about 8169.9774173495. The cubic root of 66748531 is about 405.6460369525.

The spelling of 66748531 in words is "sixty-six million, seven hundred forty-eight thousand, five hundred thirty-one".