20421440442 has 32 divisors (see below), whose sum is σ = 48871824960. Its totient is φ = 6283519920.

The previous prime is 20421440437. The next prime is 20421440447. The reversal of 20421440442 is 24404412402.

20421440442 is a `hidden beast` number, since 2 + 0 + 4 + 214 + 4 + 0 + 442 = 666.

It is an interprime number because it is at equal distance from previous prime (20421440437) and next prime (20421440447).

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

It is not an unprimeable number, because it can be changed into a prime (20421440447) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 14544484 + ... + 14545887.

It is an arithmetic number, because the mean of its divisors is an integer number (1527244530).

Almost surely, 2^20421440442 is an apocalyptic number.

20421440442 is an abundant number, since it is smaller than the sum of its proper divisors (28450384518).

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

20421440442 is a wasteful number, since it uses less digits than its factorization.

20421440442 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 29090395 (or 29090389 counting only the distinct ones).

The product of its (nonzero) digits is 8192, while the sum is 27.

Adding to 20421440442 its reverse (24404412402), we get a palindrome (44825852844).

The spelling of 20421440442 in words is "twenty billion, four hundred twenty-one million, four hundred forty thousand, four hundred forty-two".