21018654234 has 48 divisors (see below), whose sum is σ = 46118872800. Its totient is φ = 6917335008.

The previous prime is 21018654233. The next prime is 21018654257. The reversal of 21018654234 is 43245681012.

It is a happy number.

21018654234 is a `hidden beast` number, since 2 + 1 + 0 + 1 + 86 + 542 + 34 = 666.

It is a super-2 number, since 2×21018654234² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21018654233) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 2953072 + ... + 2960180.

It is an arithmetic number, because the mean of its divisors is an integer number (960809850).

Almost surely, 2^21018654234 is an apocalyptic number.

21018654234 is an abundant number, since it is smaller than the sum of its proper divisors (25100218566).

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

21018654234 is a wasteful number, since it uses less digits than its factorization.

21018654234 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9179 (or 9176 counting only the distinct ones).

The product of its (nonzero) digits is 46080, while the sum is 36.

The spelling of 21018654234 in words is "twenty-one billion, eighteen million, six hundred fifty-four thousand, two hundred thirty-four".