70391 has 4 divisors (see below), whose sum is σ = 72072. Its totient is φ = 68712.

The previous prime is 70381. The next prime is 70393. The reversal of 70391 is 19307.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 19307 = 43 ⋅449.

It is a cyclic number.

It is not a de Polignac number, because 70391 - 2⁶ = 70327 is a prime.

It is a Duffinian number.

It is a plaindrome in base 12.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (70393) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 776 + ... + 861.

It is an arithmetic number, because the mean of its divisors is an integer number (18018).

2⁷⁰³⁹¹ is an apocalyptic number.

70391 is a deficient number, since it is larger than the sum of its proper divisors (1681).

70391 is a wasteful number, since it uses less digits than its factorization.

70391 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1680.

The product of its (nonzero) digits is 189, while the sum is 20.

The square root of 70391 is about 265.3130226732. The cubic root of 70391 is about 41.2894449749.

Adding to 70391 its reverse (19307), we get a palindrome (89698).

The spelling of 70391 in words is "seventy thousand, three hundred ninety-one".