21053358 has 20 divisors (see below), whose sum is σ = 47175480. Its totient is φ = 7017732.

The previous prime is 21053353. The next prime is 21053381. The reversal of 21053358 is 85335012.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21053353) by changing a digit.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 64818 + ... + 65141.

It is an arithmetic number, because the mean of its divisors is an integer number (2358774).

Almost surely, 2^21053358 is an apocalyptic number.

21053358 is an abundant number, since it is smaller than the sum of its proper divisors (26122122).

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

21053358 is a wasteful number, since it uses less digits than its factorization.

21053358 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 129973 (or 129964 counting only the distinct ones).

The product of its (nonzero) digits is 3600, while the sum is 27.

The square root of 21053358 is about 4588.3938366274. The cubic root of 21053358 is about 276.1258877516.

The spelling of 21053358 in words is "twenty-one million, fifty-three thousand, three hundred fifty-eight".