820006651 has 4 divisors (see below), whose sum is σ = 820389672. Its totient is φ = 819623632.

The previous prime is 820006631. The next prime is 820006661. The reversal of 820006651 is 156600028.

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 820006651 - 2¹⁷ = 819875579 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (820006631) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 188281 + ... + 192586.

It is an arithmetic number, because the mean of its divisors is an integer number (205097418).

Almost surely, 2^820006651 is an apocalyptic number.

820006651 is a deficient number, since it is larger than the sum of its proper divisors (383021).

820006651 is a wasteful number, since it uses less digits than its factorization.

820006651 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 383020.

The product of its (nonzero) digits is 2880, while the sum is 28.

The square root of 820006651 is about 28635.7582578147. The cubic root of 820006651 is about 935.9926929051.

Adding to 820006651 its reverse (156600028), we get a palindrome (976606679).

The spelling of 820006651 in words is "eight hundred twenty million, six thousand, six hundred fifty-one".