70505891 has 4 divisors (see below), whose sum is σ = 70529400. Its totient is φ = 70482384.

The previous prime is 70505881. The next prime is 70505917. The reversal of 70505891 is 19850507.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 19850507 = 383 ⋅51829.

It is a cyclic number.

It is not a de Polignac number, because 70505891 - 2²² = 66311587 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (70505881) 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, 6461 + ... + 13518.

It is an arithmetic number, because the mean of its divisors is an integer number (17632350).

Almost surely, 2^70505891 is an apocalyptic number.

70505891 is a deficient number, since it is larger than the sum of its proper divisors (23509).

70505891 is a wasteful number, since it uses less digits than its factorization.

70505891 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23508.

The product of its (nonzero) digits is 12600, while the sum is 35.

The square root of 70505891 is about 8396.7786084903. The cubic root of 70505891 is about 413.1189674217.

The spelling of 70505891 in words is "seventy million, five hundred five thousand, eight hundred ninety-one".