66523403 has 2 divisors, whose sum is σ = 66523404. Its totient is φ = 66523402.

The previous prime is 66523393. The next prime is 66523409. The reversal of 66523403 is 30432566.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-66523403 is a prime.

It is not a weakly prime, because it can be changed into another prime (66523409) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33261701 + 33261702.

It is an arithmetic number, because the mean of its divisors is an integer number (33261702).

Almost surely, 2^66523403 is an apocalyptic number.

66523403 is a deficient number, since it is larger than the sum of its proper divisors (1).

66523403 is an equidigital number, since it uses as much as digits as its factorization.

66523403 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 12960, while the sum is 29.

The square root of 66523403 is about 8156.1880189216. The cubic root of 66523403 is about 405.1894718797.

Adding to 66523403 its reverse (30432566), we get a palindrome (96955969).

The spelling of 66523403 in words is "sixty-six million, five hundred twenty-three thousand, four hundred three".