681619534 has 4 divisors (see below), whose sum is σ = 1022429304. Its totient is φ = 340809766.

The previous prime is 681619517. The next prime is 681619553. The reversal of 681619534 is 435916186.

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

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 170404882 + ... + 170404885.

It is an arithmetic number, because the mean of its divisors is an integer number (255607326).

Almost surely, 2^681619534 is an apocalyptic number.

681619534 is a deficient number, since it is larger than the sum of its proper divisors (340809770).

681619534 is a wasteful number, since it uses less digits than its factorization.

681619534 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 340809769.

The product of its digits is 155520, while the sum is 43.

The square root of 681619534 is about 26107.8443001332. The cubic root of 681619534 is about 880.0635000665.

The spelling of 681619534 in words is "six hundred eighty-one million, six hundred nineteen thousand, five hundred thirty-four".