21315598 has 4 divisors (see below), whose sum is σ = 31973400. Its totient is φ = 10657798.

The previous prime is 21315583. The next prime is 21315599. The reversal of 21315598 is 89551312.

It is a semiprime because it is the product of two primes.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21315599) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5328898 + ... + 5328901.

It is an arithmetic number, because the mean of its divisors is an integer number (7993350).

Almost surely, 2^21315598 is an apocalyptic number.

21315598 is a deficient number, since it is larger than the sum of its proper divisors (10657802).

21315598 is a wasteful number, since it uses less digits than its factorization.

21315598 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10657801.

The product of its digits is 10800, while the sum is 34.

The square root of 21315598 is about 4616.8818481742. The cubic root of 21315598 is about 277.2676322242.

The spelling of 21315598 in words is "twenty-one million, three hundred fifteen thousand, five hundred ninety-eight".