21215034988 has 24 divisors (see below), whose sum is σ = 43576830752. Its totient is φ = 8846423424.

The previous prime is 21215034979. The next prime is 21215035003. The reversal of 21215034988 is 88943051212.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 10237881 + ... + 10239952.

Almost surely, 2^21215034988 is an apocalyptic number.

21215034988 is a gapful number since it is divisible by the number (28) formed by its first and last digit.

It is an amenable number.

21215034988 is an abundant number, since it is smaller than the sum of its proper divisors (22361795764).

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

21215034988 is a wasteful number, since it uses less digits than its factorization.

21215034988 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20477881 (or 20477879 counting only the distinct ones).

The product of its (nonzero) digits is 138240, while the sum is 43.

The spelling of 21215034988 in words is "twenty-one billion, two hundred fifteen million, thirty-four thousand, nine hundred eighty-eight".