20865747420 has 360 divisors, whose sum is σ = 77926940784. Its totient is φ = 4657637376.

The previous prime is 20865747349. The next prime is 20865747467. The reversal of 20865747420 is 2474756802.

It is a happy number.

20865747420 is a `hidden beast` number, since 2 + 0 + 8 + 6 + 574 + 74 + 2 + 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 polite number, since it can be written in 119 ways as a sum of consecutive naturals, for example, 3410284 + ... + 3416396.

Almost surely, 2^20865747420 is an apocalyptic number.

20865747420 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 20865747420, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (38963470392).

20865747420 is an abundant number, since it is smaller than the sum of its proper divisors (57061193364).

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

20865747420 is a wasteful number, since it uses less digits than its factorization.

20865747420 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6191 (or 6173 counting only the distinct ones).

The product of its (nonzero) digits is 752640, while the sum is 45.

The spelling of 20865747420 in words is "twenty billion, eight hundred sixty-five million, seven hundred forty-seven thousand, four hundred twenty".