70891381 has 4 divisors (see below), whose sum is σ = 77336064. Its totient is φ = 64446700.

The previous prime is 70891367. The next prime is 70891439. The reversal of 70891381 is 18319807.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 18319807 = 11 ⋅1665437.

It is a cyclic number.

It is not a de Polignac number, because 70891381 - 2⁵ = 70891349 is a prime.

It is a super-2 number, since 2×70891381² = 10051175800174322, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 70891381.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (70891321) 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, 3222325 + ... + 3222346.

It is an arithmetic number, because the mean of its divisors is an integer number (19334016).

Almost surely, 2^70891381 is an apocalyptic number.

It is an amenable number.

70891381 is a deficient number, since it is larger than the sum of its proper divisors (6444683).

70891381 is a wasteful number, since it uses less digits than its factorization.

70891381 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6444682.

The product of its (nonzero) digits is 12096, while the sum is 37.

The square root of 70891381 is about 8419.7019543449. The cubic root of 70891381 is about 413.8705068491.

The spelling of 70891381 in words is "seventy million, eight hundred ninety-one thousand, three hundred eighty-one".