70018391 has 4 divisors (see below), whose sum is σ = 71508192. Its totient is φ = 68528592.

The previous prime is 70018387. The next prime is 70018409. The reversal of 70018391 is 19381007.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 70018391 - 2² = 70018387 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (70018691) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 744830 + ... + 744923.

It is an arithmetic number, because the mean of its divisors is an integer number (17877048).

Almost surely, 2^70018391 is an apocalyptic number.

70018391 is a deficient number, since it is larger than the sum of its proper divisors (1489801).

70018391 is a wasteful number, since it uses less digits than its factorization.

70018391 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1489800.

The product of its (nonzero) digits is 1512, while the sum is 29.

The square root of 70018391 is about 8367.6992656285. The cubic root of 70018391 is about 412.1646194671.

Adding to 70018391 its reverse (19381007), we get a palindrome (89399398).

It can be divided in two parts, 700 and 18391, that added together give a palindrome (19091).

The spelling of 70018391 in words is "seventy million, eighteen thousand, three hundred ninety-one".