20855439630 has 32 divisors (see below), whose sum is σ = 55614506400. Its totient is φ = 5561450496.

The previous prime is 20855439629. The next prime is 20855439667. The reversal of 20855439630 is 3693455802.

20855439630 is a `hidden beast` number, since 2 + 0 + 8 + 5 + 5 + 4 + 3 + 9 + 630 = 666.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 38620915 + ... + 38621454.

It is an arithmetic number, because the mean of its divisors is an integer number (1737953325).

Almost surely, 2^20855439630 is an apocalyptic number.

20855439630 is an abundant number, since it is smaller than the sum of its proper divisors (34759066770).

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

20855439630 is a wasteful number, since it uses less digits than its factorization.

20855439630 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 77242385 (or 77242379 counting only the distinct ones).

The product of its (nonzero) digits is 777600, while the sum is 45.

The spelling of 20855439630 in words is "twenty billion, eight hundred fifty-five million, four hundred thirty-nine thousand, six hundred thirty".