70666021 has 2 divisors, whose sum is σ = 70666022. Its totient is φ = 70666020.

The previous prime is 70666009. The next prime is 70666049. The reversal of 70666021 is 12066607.

It is an a-pointer prime, because the next prime (70666049) can be obtained adding 70666021 to its sum of digits (28).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 60233121 + 10432900 = 7761^2 + 3230^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-70666021 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (70666061) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 35333010 + 35333011.

It is an arithmetic number, because the mean of its divisors is an integer number (35333011).

Almost surely, 2^70666021 is an apocalyptic number.

It is an amenable number.

70666021 is a deficient number, since it is larger than the sum of its proper divisors (1).

70666021 is an equidigital number, since it uses as much as digits as its factorization.

70666021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3024, while the sum is 28.

The square root of 70666021 is about 8406.3084050016. The cubic root of 70666021 is about 413.4314837297.

The spelling of 70666021 in words is "seventy million, six hundred sixty-six thousand, twenty-one".