21146020 has 48 divisors (see below), whose sum is σ = 51182208. Its totient is φ = 7188480.

The previous prime is 21145991. The next prime is 21146023. The reversal of 21146020 is 2064112.

It is a junction number, because it is equal to n+sod(n) for n = 21145985 and 21146003.

It is not an unprimeable number, because it can be changed into a prime (21146023) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 17764 + ... + 18916.

It is an arithmetic number, because the mean of its divisors is an integer number (1066296).

Almost surely, 2^21146020 is an apocalyptic number.

21146020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21146020, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25591104).

21146020 is an abundant number, since it is smaller than the sum of its proper divisors (30036188).

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

21146020 is a wasteful number, since it uses less digits than its factorization.

21146020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1300 (or 1298 counting only the distinct ones).

The product of its (nonzero) digits is 96, while the sum is 16.

The square root of 21146020 is about 4598.4801837129. The cubic root of 21146020 is about 276.5303985318.

The spelling of 21146020 in words is "twenty-one million, one hundred forty-six thousand, twenty".