690785881 has 4 divisors (see below), whose sum is σ = 694645200. Its totient is φ = 686926564.

The previous prime is 690785863. The next prime is 690785897. The reversal of 690785881 is 188587096.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 690785881 - 2¹¹ = 690783833 is a prime.

It is a super-2 number, since 2×690785881² = 954370266777892322, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (690785801) 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, 1929391 + ... + 1929748.

It is an arithmetic number, because the mean of its divisors is an integer number (173661300).

Almost surely, 2^690785881 is an apocalyptic number.

It is an amenable number.

690785881 is a deficient number, since it is larger than the sum of its proper divisors (3859319).

690785881 is a wasteful number, since it uses less digits than its factorization.

690785881 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3859318.

The product of its (nonzero) digits is 967680, while the sum is 52.

The square root of 690785881 is about 26282.8058053169. The cubic root of 690785881 is about 883.9909471477.

The spelling of 690785881 in words is "six hundred ninety million, seven hundred eighty-five thousand, eight hundred eighty-one".