20465643870 has 160 divisors (see below), whose sum is σ = 64591674048. Its totient is φ = 4551386112.

The previous prime is 20465643791. The next prime is 20465643881. The reversal of 20465643870 is 7834656402.

20465643870 is a `hidden beast` number, since 2 + 0 + 4 + 6 + 564 + 3 + 87 + 0 = 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 pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 161014 + ... + 258566.

Almost surely, 2^20465643870 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20465643870, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (32295837024).

20465643870 is an abundant number, since it is smaller than the sum of its proper divisors (44126030178).

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

20465643870 is a wasteful number, since it uses less digits than its factorization.

20465643870 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 97616 (or 97607 counting only the distinct ones).

The product of its (nonzero) digits is 967680, while the sum is 45.

The spelling of 20465643870 in words is "twenty billion, four hundred sixty-five million, six hundred forty-three thousand, eight hundred seventy".