21134278747128 has 32 divisors (see below), whose sum is σ = 52928228770560. Its totient is φ = 7032421995360.

The previous prime is 21134278747117. The next prime is 21134278747129. The reversal of 21134278747128 is 82174787243112.

It is a happy number.

It is a super-2 number, since 2×21134278747128² (a number of 27 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21134278747129) 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, 771085200 + ... + 771112607.

It is an arithmetic number, because the mean of its divisors is an integer number (1654007149080).

Almost surely, 2^{21134278747128} is an apocalyptic number.

It is an amenable number.

21134278747128 is an abundant number, since it is smaller than the sum of its proper divisors (31793950023432).

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

21134278747128 is a wasteful number, since it uses less digits than its factorization.

21134278747128 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1542198387 (or 1542198383 counting only the distinct ones).

The product of its digits is 8429568, while the sum is 57.

The spelling of 21134278747128 in words is "twenty-one trillion, one hundred thirty-four billion, two hundred seventy-eight million, seven hundred forty-seven thousand, one hundred twenty-eight".