70987831 has 4 divisors (see below), whose sum is σ = 71005464. Its totient is φ = 70970200.

The previous prime is 70987823. The next prime is 70987841. The reversal of 70987831 is 13878907.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 70987831 - 2³ = 70987823 is a prime.

It is a super-2 number, since 2×70987831² = 10078544300169122, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (70987811) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 516 + ... + 11926.

It is an arithmetic number, because the mean of its divisors is an integer number (17751366).

Almost surely, 2^70987831 is an apocalyptic number.

70987831 is a deficient number, since it is larger than the sum of its proper divisors (17633).

70987831 is a wasteful number, since it uses less digits than its factorization.

70987831 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17632.

The product of its (nonzero) digits is 84672, while the sum is 43.

The square root of 70987831 is about 8425.4276449329. The cubic root of 70987831 is about 414.0581164961.

The spelling of 70987831 in words is "seventy million, nine hundred eighty-seven thousand, eight hundred thirty-one".