21157063 has 8 divisors (see below), whose sum is σ = 21450240. Its totient is φ = 20866200.

The previous prime is 21157049. The next prime is 21157067. The reversal of 21157063 is 36075112.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21157063 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21157067) 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, 24798 + ... + 25636.

It is an arithmetic number, because the mean of its divisors is an integer number (2681280).

Almost surely, 2^21157063 is an apocalyptic number.

21157063 is a deficient number, since it is larger than the sum of its proper divisors (293177).

21157063 is a wasteful number, since it uses less digits than its factorization.

21157063 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1157.

The product of its (nonzero) digits is 1260, while the sum is 25.

The square root of 21157063 is about 4599.6807497912. The cubic root of 21157063 is about 276.5785272698.

The spelling of 21157063 in words is "twenty-one million, one hundred fifty-seven thousand, sixty-three".