21887355855020 has 24 divisors (see below), whose sum is σ = 46649468899824. Its totient is φ = 8624271560256.

The previous prime is 21887355855017. The next prime is 21887355855023. The reversal of 21887355855020 is 2055855378812.

It is an interprime number because it is at equal distance from previous prime (21887355855017) and next prime (21887355855023).

It is not an unprimeable number, because it can be changed into a prime (21887355855023) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 8166922487 + ... + 8166925166.

It is an arithmetic number, because the mean of its divisors is an integer number (1943727870826).

Almost surely, 2^{21887355855020} is an apocalyptic number.

21887355855020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21887355855020 is an abundant number, since it is smaller than the sum of its proper divisors (24762113044804).

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

21887355855020 is a wasteful number, since it uses less digits than its factorization.

21887355855020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16333847729 (or 16333847727 counting only the distinct ones).

The product of its (nonzero) digits is 26880000, while the sum is 59.

The spelling of 21887355855020 in words is "twenty-one trillion, eight hundred eighty-seven billion, three hundred fifty-five million, eight hundred fifty-five thousand, twenty".