70135821 has 32 divisors (see below), whose sum is σ = 125004800. Its totient is φ = 37966320.

The previous prime is 70135739. The next prime is 70135841. The reversal of 70135821 is 12853107.

70135821 is a `hidden beast` number, since 70 + 13 + 582 + 1 = 666.

It is not a de Polignac number, because 70135821 - 2¹⁸ = 69873677 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (70135841) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 6175 + ... + 13356.

It is an arithmetic number, because the mean of its divisors is an integer number (3906400).

Almost surely, 2^70135821 is an apocalyptic number.

It is an amenable number.

70135821 is a deficient number, since it is larger than the sum of its proper divisors (54868979).

70135821 is a wasteful number, since it uses less digits than its factorization.

70135821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19566 (or 19560 counting only the distinct ones).

The product of its (nonzero) digits is 1680, while the sum is 27.

The square root of 70135821 is about 8374.7131891188. The cubic root of 70135821 is about 412.3949087657.

Adding to 70135821 its reverse (12853107), we get a palindrome (82988928).

The spelling of 70135821 in words is "seventy million, one hundred thirty-five thousand, eight hundred twenty-one".