820698993 has 32 divisors (see below), whose sum is σ = 1235520000. Its totient is φ = 538344576.

The previous prime is 820698973. The next prime is 820699001. The reversal of 820698993 is 399896028.

It is not a de Polignac number, because 820698993 - 2¹⁷ = 820567921 is a prime.

It is a super-2 number, since 2×820698993² = 1347093674222428098, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (820698973) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 573603 + ... + 575031.

It is an arithmetic number, because the mean of its divisors is an integer number (38610000).

Almost surely, 2^820698993 is an apocalyptic number.

It is an amenable number.

820698993 is a deficient number, since it is larger than the sum of its proper divisors (414821007).

820698993 is a wasteful number, since it uses less digits than its factorization.

820698993 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1766 (or 1760 counting only the distinct ones).

The product of its (nonzero) digits is 1679616, while the sum is 54.

The square root of 820698993 is about 28647.8444738867. The cubic root of 820698993 is about 936.2560422972.

The spelling of 820698993 in words is "eight hundred twenty million, six hundred ninety-eight thousand, nine hundred ninety-three".