70642391 has 2 divisors, whose sum is σ = 70642392. Its totient is φ = 70642390.

The previous prime is 70642357. The next prime is 70642393. The reversal of 70642391 is 19324607.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-70642391 is a prime.

Together with 70642393, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (70642393) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 35321195 + 35321196.

It is an arithmetic number, because the mean of its divisors is an integer number (35321196).

Almost surely, 2^70642391 is an apocalyptic number.

70642391 is a deficient number, since it is larger than the sum of its proper divisors (1).

70642391 is an equidigital number, since it uses as much as digits as its factorization.

70642391 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 9072, while the sum is 32.

The square root of 70642391 is about 8404.9027953927. The cubic root of 70642391 is about 413.3853961619.

Adding to 70642391 its reverse (19324607), we get a palindrome (89966998).

The spelling of 70642391 in words is "seventy million, six hundred forty-two thousand, three hundred ninety-one".