20854491840 has 504 divisors, whose sum is σ = 88783594848. Its totient is φ = 4399349760.

The previous prime is 20854491773. The next prime is 20854491841. The reversal of 20854491840 is 4819445802.

20854491840 is a `hidden beast` number, since 2 + 0 + 85 + 4 + 491 + 84 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (504).

It is a Harshad number since it is a multiple of its sum of digits (45).

It is not an unprimeable number, because it can be changed into a prime (20854491841) by changing a digit.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 3403980 + ... + 3410100.

Almost surely, 2^20854491840 is an apocalyptic number.

20854491840 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20854491840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (44391797424).

20854491840 is an abundant number, since it is smaller than the sum of its proper divisors (67929103008).

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

20854491840 is a wasteful number, since it uses less digits than its factorization.

20854491840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6177 (or 6151 counting only the distinct ones).

The product of its (nonzero) digits is 368640, while the sum is 45.

The spelling of 20854491840 in words is "twenty billion, eight hundred fifty-four million, four hundred ninety-one thousand, eight hundred forty".