20421596 has 12 divisors (see below), whose sum is σ = 38486952. Its totient is φ = 9425328.

The previous prime is 20421593. The next prime is 20421629. The reversal of 20421596 is 69512402.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20421593) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 196310 + ... + 196413.

It is an arithmetic number, because the mean of its divisors is an integer number (3207246).

Almost surely, 2^20421596 is an apocalyptic number.

20421596 is a gapful number since it is divisible by the number (26) formed by its first and last digit.

It is an amenable number.

20421596 is a deficient number, since it is larger than the sum of its proper divisors (18065356).

20421596 is a wasteful number, since it uses less digits than its factorization.

20421596 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 392740 (or 392738 counting only the distinct ones).

The product of its (nonzero) digits is 4320, while the sum is 29.

The square root of 20421596 is about 4519.0260012529. The cubic root of 20421596 is about 273.3358271965.

Adding to 20421596 its reverse (69512402), we get a palindrome (89933998).

The spelling of 20421596 in words is "twenty million, four hundred twenty-one thousand, five hundred ninety-six".