20218421340 has 576 divisors, whose sum is σ = 72775301760. Its totient is φ = 4686128640.

The previous prime is 20218421281. The next prime is 20218421357. The reversal of 20218421340 is 4312481202.

20218421340 is a `hidden beast` number, since 20 + 218 + 421 + 3 + 4 + 0 = 666.

It is a super-2 number, since 2×20218421340² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 546443802 + ... + 546443838.

It is an arithmetic number, because the mean of its divisors is an integer number (126346010).

Almost surely, 2^20218421340 is an apocalyptic number.

20218421340 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 20218421340, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (36387650880).

20218421340 is an abundant number, since it is smaller than the sum of its proper divisors (52556880420).

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

20218421340 is a wasteful number, since it uses less digits than its factorization.

20218421340 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 142 (or 91 counting only the distinct ones).

The product of its (nonzero) digits is 3072, while the sum is 27.

The spelling of 20218421340 in words is "twenty billion, two hundred eighteen million, four hundred twenty-one thousand, three hundred forty".