245686821 has 8 divisors (see below), whose sum is σ = 335200800. Its totient is φ = 159982032.

The previous prime is 245686807. The next prime is 245686823. The reversal of 245686821 is 128686542.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 245686821 - 2²⁷ = 111469093 is a prime.

It is a Smith number, since the sum of its digits (42) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (245686823) 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 7 ways as a sum of consecutive naturals, for example, 952146 + ... + 952403.

It is an arithmetic number, because the mean of its divisors is an integer number (41900100).

Almost surely, 2^245686821 is an apocalyptic number.

It is an amenable number.

245686821 is a deficient number, since it is larger than the sum of its proper divisors (89513979).

245686821 is a wasteful number, since it uses less digits than its factorization.

245686821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1904595.

The product of its digits is 184320, while the sum is 42.

The square root of 245686821 is about 15674.4001799112. The cubic root of 245686821 is about 626.3166449527.

The spelling of 245686821 in words is "two hundred forty-five million, six hundred eighty-six thousand, eight hundred twenty-one".