666121071 has 16 divisors (see below), whose sum is σ = 1107318528. Its totient is φ = 346036800.

The previous prime is 666121069. The next prime is 666121091. The reversal of 666121071 is 170121666.

It is not a de Polignac number, because 666121071 - 2¹ = 666121069 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (666121031) 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, 1441590 + ... + 1442051.

It is an arithmetic number, because the mean of its divisors is an integer number (69207408).

Almost surely, 2^666121071 is an apocalyptic number.

666121071 is a deficient number, since it is larger than the sum of its proper divisors (441197457).

666121071 is a wasteful number, since it uses less digits than its factorization.

666121071 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2883662.

The product of its (nonzero) digits is 3024, while the sum is 30.

The square root of 666121071 is about 25809.3213975106. The cubic root of 666121071 is about 873.3420888380.

The spelling of 666121071 in words is "six hundred sixty-six million, one hundred twenty-one thousand, seventy-one".