20954198509 has 8 divisors (see below), whose sum is σ = 21228141312. Its totient is φ = 20680767360.

The previous prime is 20954198491. The next prime is 20954198527. The reversal of 20954198509 is 90589145902.

It is an interprime number because it is at equal distance from previous prime (20954198491) and next prime (20954198527).

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 20954198509 - 2¹⁷ = 20954067437 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 (20954198539) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 45124 + ... + 209629.

It is an arithmetic number, because the mean of its divisors is an integer number (2653517664).

Almost surely, 2^20954198509 is an apocalyptic number.

It is an amenable number.

20954198509 is a deficient number, since it is larger than the sum of its proper divisors (273942803).

20954198509 is an equidigital number, since it uses as much as digits as its factorization.

20954198509 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 255827.

The product of its (nonzero) digits is 1166400, while the sum is 52.

The spelling of 20954198509 in words is "twenty billion, nine hundred fifty-four million, one hundred ninety-eight thousand, five hundred nine".