820606651 has 4 divisors (see below), whose sum is σ = 831847912. Its totient is φ = 809365392.

The previous prime is 820606607. The next prime is 820606667. The reversal of 820606651 is 156606028.

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 820606651 - 2¹³ = 820598459 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (820606691) 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, 5620521 + ... + 5620666.

It is an arithmetic number, because the mean of its divisors is an integer number (207961978).

Almost surely, 2^820606651 is an apocalyptic number.

820606651 is a deficient number, since it is larger than the sum of its proper divisors (11241261).

820606651 is a wasteful number, since it uses less digits than its factorization.

820606651 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11241260.

The product of its (nonzero) digits is 17280, while the sum is 34.

The square root of 820606651 is about 28646.2327540638. The cubic root of 820606651 is about 936.2209262969.

The spelling of 820606651 in words is "eight hundred twenty million, six hundred six thousand, six hundred fifty-one".