2199700781 has 4 divisors (see below), whose sum is σ = 2213711772. Its totient is φ = 2185689792.

The previous prime is 2199700753. The next prime is 2199700807. The reversal of 2199700781 is 1870079912.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 1681410025 + 518290756 = 41005^2 + 22766^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2199700781 is a prime.

It is a super-2 number, since 2×2199700781² = 9677367051864019922, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2199700681) 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, 7005260 + ... + 7005573.

It is an arithmetic number, because the mean of its divisors is an integer number (553427943).

Almost surely, 2^2199700781 is an apocalyptic number.

It is an amenable number.

2199700781 is a deficient number, since it is larger than the sum of its proper divisors (14010991).

2199700781 is a wasteful number, since it uses less digits than its factorization.

2199700781 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14010990.

The product of its (nonzero) digits is 63504, while the sum is 44.

The square root of 2199700781 is about 46900.9678045134. The cubic root of 2199700781 is about 1300.5324802883.

The spelling of 2199700781 in words is "two billion, one hundred ninety-nine million, seven hundred thousand, seven hundred eighty-one".