70213921 has 2 divisors, whose sum is σ = 70213922. Its totient is φ = 70213920.

The previous prime is 70213907. The next prime is 70213931. The reversal of 70213921 is 12931207.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 41473600 + 28740321 = 6440^2 + 5361^2 .

It is a cyclic number.

It is not a de Polignac number, because 70213921 - 2⁵ = 70213889 is a prime.

It is not a weakly prime, because it can be changed into another prime (70213931) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 35106960 + 35106961.

It is an arithmetic number, because the mean of its divisors is an integer number (35106961).

Almost surely, 2^70213921 is an apocalyptic number.

It is an amenable number.

70213921 is a deficient number, since it is larger than the sum of its proper divisors (1).

70213921 is an equidigital number, since it uses as much as digits as its factorization.

70213921 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 756, while the sum is 25.

The square root of 70213921 is about 8379.3747380100. The cubic root of 70213921 is about 412.5479266016.

The spelling of 70213921 in words is "seventy million, two hundred thirteen thousand, nine hundred twenty-one".