1660959221 has 2 divisors, whose sum is σ = 1660959222. Its totient is φ = 1660959220.

The previous prime is 1660959217. The next prime is 1660959259. The reversal of 1660959221 is 1229590661.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1526074225 + 134884996 = 39065^2 + 11614^2 .

It is a cyclic number.

It is not a de Polignac number, because 1660959221 - 2² = 1660959217 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1660955221) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 830479610 + 830479611.

It is an arithmetic number, because the mean of its divisors is an integer number (830479611).

Almost surely, 2^1660959221 is an apocalyptic number.

It is an amenable number.

1660959221 is a deficient number, since it is larger than the sum of its proper divisors (1).

1660959221 is an equidigital number, since it uses as much as digits as its factorization.

1660959221 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 58320, while the sum is 41.

The square root of 1660959221 is about 40754.8674516309. The cubic root of 1660959221 is about 1184.2761686581.

The spelling of 1660959221 in words is "one billion, six hundred sixty million, nine hundred fifty-nine thousand, two hundred twenty-one".