66211901 has 16 divisors (see below), whose sum is σ = 79578240. Its totient is φ = 53887680.

The previous prime is 66211867. The next prime is 66211913. The reversal of 66211901 is 10911266.

It is not a de Polignac number, because 66211901 - 2⁶ = 66211837 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66211001) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 9710 + ... + 15056.

It is an arithmetic number, because the mean of its divisors is an integer number (4973640).

Almost surely, 2^66211901 is an apocalyptic number.

66211901 is a gapful number since it is divisible by the number (61) formed by its first and last digit.

It is an amenable number.

66211901 is a deficient number, since it is larger than the sum of its proper divisors (13366339).

66211901 is a wasteful number, since it uses less digits than its factorization.

66211901 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5444.

The product of its (nonzero) digits is 648, while the sum is 26.

The square root of 66211901 is about 8137.0695585081. The cubic root of 66211901 is about 404.5560363898.

The spelling of 66211901 in words is "sixty-six million, two hundred eleven thousand, nine hundred one".