21495138 has 32 divisors (see below), whose sum is σ = 49351680. Its totient is φ = 6114000.

The previous prime is 21495107. The next prime is 21495143. The reversal of 21495138 is 83159412.

It is a junction number, because it is equal to n+sod(n) for n = 21495099 and 21495108.

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, 9523 + ... + 11561.

It is an arithmetic number, because the mean of its divisors is an integer number (1542240).

Almost surely, 2^21495138 is an apocalyptic number.

21495138 is an abundant number, since it is smaller than the sum of its proper divisors (27856542).

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

21495138 is a wasteful number, since it uses less digits than its factorization.

21495138 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2302.

The product of its digits is 8640, while the sum is 33.

The square root of 21495138 is about 4636.2849351609. The cubic root of 21495138 is about 278.0439262577.

The spelling of 21495138 in words is "twenty-one million, four hundred ninety-five thousand, one hundred thirty-eight".