21420696 has 64 divisors (see below), whose sum is σ = 59875200. Its totient is φ = 6329600.

The previous prime is 21420683. The next prime is 21420703. The reversal of 21420696 is 69602412.

It is a congruent number.

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, 9835 + ... + 11813.

It is an arithmetic number, because the mean of its divisors is an integer number (935550).

Almost surely, 2^21420696 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21420696, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29937600).

21420696 is an abundant number, since it is smaller than the sum of its proper divisors (38454504).

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

21420696 is a wasteful number, since it uses less digits than its factorization.

21420696 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2040 (or 2036 counting only the distinct ones).

The product of its (nonzero) digits is 5184, while the sum is 30.

The square root of 21420696 is about 4628.2497771836. The cubic root of 21420696 is about 277.7225809378.

It can be divided in two parts, 214 and 20696, that added together give a triangular number (20910 = T₂₀₄).

The spelling of 21420696 in words is "twenty-one million, four hundred twenty thousand, six hundred ninety-six".