21002471016 has 64 divisors (see below), whose sum is σ = 52899739200. Its totient is φ = 6948523008.

The previous prime is 21002470921. The next prime is 21002471023. The reversal of 21002471016 is 61017420012.

It is a super-2 number, since 2×21002471016² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2042095 + ... + 2052353.

It is an arithmetic number, because the mean of its divisors is an integer number (826558425).

Almost surely, 2^21002471016 is an apocalyptic number.

It is an amenable number.

21002471016 is an abundant number, since it is smaller than the sum of its proper divisors (31897268184).

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

21002471016 is a wasteful number, since it uses less digits than its factorization.

21002471016 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10898 (or 10894 counting only the distinct ones).

The product of its (nonzero) digits is 672, while the sum is 24.

Adding to 21002471016 its reverse (61017420012), we get a palindrome (82019891028).

The spelling of 21002471016 in words is "twenty-one billion, two million, four hundred seventy-one thousand, sixteen".