66536551 has 2 divisors, whose sum is σ = 66536552. Its totient is φ = 66536550.

The previous prime is 66536479. The next prime is 66536567. The reversal of 66536551 is 15563566.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-66536551 is a prime.

It is a super-2 number, since 2×66536551² = 8854225237951202, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 66536551.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (66536581) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33268275 + 33268276.

It is an arithmetic number, because the mean of its divisors is an integer number (33268276).

Almost surely, 2^66536551 is an apocalyptic number.

66536551 is a deficient number, since it is larger than the sum of its proper divisors (1).

66536551 is an equidigital number, since it uses as much as digits as its factorization.

66536551 is an evil number, because the sum of its binary digits is even.

The product of its digits is 81000, while the sum is 37.

The square root of 66536551 is about 8156.9939928873. The cubic root of 66536551 is about 405.2161646424.

The spelling of 66536551 in words is "sixty-six million, five hundred thirty-six thousand, five hundred fifty-one".