70811381 has 2 divisors, whose sum is σ = 70811382. Its totient is φ = 70811380.

The previous prime is 70811369. The next prime is 70811383. The reversal of 70811381 is 18311807.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 54538225 + 16273156 = 7385^2 + 4034^2 .

It is an emirp because it is prime and its reverse (18311807) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-70811381 is a prime.

It is a super-2 number, since 2×70811381² = 10028503358254322, which contains 22 as substring.

Together with 70811383, 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 (70811383) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 35405690 + 35405691.

It is an arithmetic number, because the mean of its divisors is an integer number (35405691).

Almost surely, 2^70811381 is an apocalyptic number.

It is an amenable number.

70811381 is a deficient number, since it is larger than the sum of its proper divisors (1).

70811381 is an equidigital number, since it uses as much as digits as its factorization.

70811381 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1344, while the sum is 29.

The square root of 70811381 is about 8414.9498513063. The cubic root of 70811381 is about 413.7147657586.

The spelling of 70811381 in words is "seventy million, eight hundred eleven thousand, three hundred eighty-one".