21010626 has 96 divisors (see below), whose sum is σ = 57028608. Its totient is φ = 5443200.

The previous prime is 21010609. The next prime is 21010663. The reversal of 21010626 is 62601012.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a junction number, because it is equal to n+sod(n) for n = 21010599 and 21010608.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 165375 + ... + 165501.

It is an arithmetic number, because the mean of its divisors is an integer number (594048).

Almost surely, 2^21010626 is an apocalyptic number.

21010626 is a gapful number since it is divisible by the number (26) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 21010626, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28514304).

21010626 is an abundant number, since it is smaller than the sum of its proper divisors (36017982).

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

21010626 is a wasteful number, since it uses less digits than its factorization.

21010626 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 256 (or 253 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 18.

The square root of 21010626 is about 4583.7349399807. The cubic root of 21010626 is about 275.9389436460.

Adding to 21010626 its reverse (62601012), we get a palindrome (83611638).

The spelling of 21010626 in words is "twenty-one million, ten thousand, six hundred twenty-six".