20867799198749 has 4 divisors (see below), whose sum is σ = 20867814127680. Its totient is φ = 20867784269820.

The previous prime is 20867799198731. The next prime is 20867799198767. The reversal of 20867799198749 is 94789199776802.

It is a happy number.

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 an interprime number because it is at equal distance from previous prime (20867799198731) and next prime (20867799198767).

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20867799198749 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20867799198349) 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, 5122907 + ... + 8244984.

It is an arithmetic number, because the mean of its divisors is an integer number (5216953531920).

Almost surely, 2^{20867799198749} is an apocalyptic number.

It is an amenable number.

20867799198749 is a deficient number, since it is larger than the sum of its proper divisors (14928931).

20867799198749 is a wasteful number, since it uses less digits than its factorization.

20867799198749 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14928930.

The product of its (nonzero) digits is 6913299456, while the sum is 86.

The spelling of 20867799198749 in words is "twenty trillion, eight hundred sixty-seven billion, seven hundred ninety-nine million, one hundred ninety-eight thousand, seven hundred forty-nine".