21053877 has 8 divisors (see below), whose sum is σ = 30231264. Its totient is φ = 12956208.

The previous prime is 21053873. The next prime is 21053887. The reversal of 21053877 is 77835012.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 21053877 - 2² = 21053873 is a prime.

It is a super-2 number, since 2×21053877² = 886531473462258, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21053873) 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, 269883 + ... + 269960.

It is an arithmetic number, because the mean of its divisors is an integer number (3778908).

Almost surely, 2^21053877 is an apocalyptic number.

It is an amenable number.

21053877 is a deficient number, since it is larger than the sum of its proper divisors (9177387).

21053877 is a wasteful number, since it uses less digits than its factorization.

21053877 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 539859.

The product of its (nonzero) digits is 11760, while the sum is 33.

The square root of 21053877 is about 4588.4503920169. The cubic root of 21053877 is about 276.1281567191.

Adding to 21053877 its reverse (77835012), we get a palindrome (98888889).

The spelling of 21053877 in words is "twenty-one million, fifty-three thousand, eight hundred seventy-seven".