70305821 has 2 divisors, whose sum is σ = 70305822. Its totient is φ = 70305820.

The previous prime is 70305811. The next prime is 70305827. The reversal of 70305821 is 12850307.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 48580900 + 21724921 = 6970^2 + 4661^2 .

It is a cyclic number.

It is not a de Polignac number, because 70305821 - 2²⁶ = 3196957 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 (70305827) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 35152910 + 35152911.

It is an arithmetic number, because the mean of its divisors is an integer number (35152911).

Almost surely, 2^70305821 is an apocalyptic number.

It is an amenable number.

70305821 is a deficient number, since it is larger than the sum of its proper divisors (1).

70305821 is an equidigital number, since it uses as much as digits as its factorization.

70305821 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1680, while the sum is 26.

The square root of 70305821 is about 8384.8566475522. The cubic root of 70305821 is about 412.7278369145.

The spelling of 70305821 in words is "seventy million, three hundred five thousand, eight hundred twenty-one".