70278721 has 2 divisors, whose sum is σ = 70278722. Its totient is φ = 70278720.

The previous prime is 70278713. The next prime is 70278737. The reversal of 70278721 is 12787207.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 58982400 + 11296321 = 7680^2 + 3361^2 .

It is an emirp because it is prime and its reverse (12787207) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 70278721 - 2³ = 70278713 is a prime.

It is not a weakly prime, because it can be changed into another prime (70278781) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 35139360 + 35139361.

It is an arithmetic number, because the mean of its divisors is an integer number (35139361).

Almost surely, 2^70278721 is an apocalyptic number.

It is an amenable number.

70278721 is a deficient number, since it is larger than the sum of its proper divisors (1).

70278721 is an equidigital number, since it uses as much as digits as its factorization.

70278721 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 10976, while the sum is 34.

The square root of 70278721 is about 8383.2404832499. The cubic root of 70278721 is about 412.6748002355.

The spelling of 70278721 in words is "seventy million, two hundred seventy-eight thousand, seven hundred twenty-one".