20909547954 has 32 divisors (see below), whose sum is σ = 46470493440. Its totient is φ = 6969124656.

The previous prime is 20909547941. The next prime is 20909547959. The reversal of 20909547954 is 45974590902.

20909547954 is a `hidden beast` number, since 2 + 0 + 9 + 0 + 9 + 547 + 95 + 4 = 666.

It is a super-2 number, since 2×20909547954² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a self number, because there is not a number n which added to its sum of digits gives 20909547954.

It is not an unprimeable number, because it can be changed into a prime (20909547959) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 845712 + ... + 870084.

It is an arithmetic number, because the mean of its divisors is an integer number (1452202920).

Almost surely, 2^20909547954 is an apocalyptic number.

20909547954 is an abundant number, since it is smaller than the sum of its proper divisors (25560945486).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20909547954 is a wasteful number, since it uses less digits than its factorization.

20909547954 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 40271 (or 40265 counting only the distinct ones).

The product of its (nonzero) digits is 4082400, while the sum is 54.

It can be divided in two parts, 209095 and 47954, that added together give a square (257049 = 507²).

The spelling of 20909547954 in words is "twenty billion, nine hundred nine million, five hundred forty-seven thousand, nine hundred fifty-four".