70881638 has 4 divisors (see below), whose sum is σ = 106322460. Its totient is φ = 35440818.

The previous prime is 70881637. The next prime is 70881641. The reversal of 70881638 is 83618807.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 83618807 = 233 ⋅358879.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 70881595 and 70881604.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (70881631) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 17720408 + ... + 17720411.

It is an arithmetic number, because the mean of its divisors is an integer number (26580615).

Almost surely, 2^70881638 is an apocalyptic number.

70881638 is a deficient number, since it is larger than the sum of its proper divisors (35440822).

70881638 is a wasteful number, since it uses less digits than its factorization.

70881638 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 35440821.

The product of its (nonzero) digits is 64512, while the sum is 41.

The square root of 70881638 is about 8419.1233510384. The cubic root of 70881638 is about 413.8515457989.

The spelling of 70881638 in words is "seventy million, eight hundred eighty-one thousand, six hundred thirty-eight".