66019501 has 2 divisors, whose sum is σ = 66019502. Its totient is φ = 66019500.

The previous prime is 66019493. The next prime is 66019511. The reversal of 66019501 is 10591066.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 39702601 + 26316900 = 6301^2 + 5130^2 .

It is a cyclic number.

It is not a de Polignac number, because 66019501 - 2³ = 66019493 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 66019501.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (66019511) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33009750 + 33009751.

It is an arithmetic number, because the mean of its divisors is an integer number (33009751).

Almost surely, 2^66019501 is an apocalyptic number.

It is an amenable number.

66019501 is a deficient number, since it is larger than the sum of its proper divisors (1).

66019501 is an equidigital number, since it uses as much as digits as its factorization.

66019501 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1620, while the sum is 28.

The square root of 66019501 is about 8125.2385195759. The cubic root of 66019501 is about 404.1638002749.

The spelling of 66019501 in words is "sixty-six million, nineteen thousand, five hundred one".