21139068 has 24 divisors (see below), whose sum is σ = 49507920. Its totient is φ = 7020160.

The previous prime is 21139061. The next prime is 21139087. The reversal of 21139068 is 86093112.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21139061) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 238 + ... + 6506.

It is an arithmetic number, because the mean of its divisors is an integer number (2062830).

Almost surely, 2^21139068 is an apocalyptic number.

It is an amenable number.

21139068 is an abundant number, since it is smaller than the sum of its proper divisors (28368852).

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

21139068 is a wasteful number, since it uses less digits than its factorization.

21139068 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6557 (or 6555 counting only the distinct ones).

The product of its (nonzero) digits is 2592, while the sum is 30.

The square root of 21139068 is about 4597.7242196548. The cubic root of 21139068 is about 276.5000910154.

The spelling of 21139068 in words is "twenty-one million, one hundred thirty-nine thousand, sixty-eight".