21050157 has 8 divisors (see below), whose sum is σ = 29544160. Its totient is φ = 13294800.

The previous prime is 21050149. The next prime is 21050171. The reversal of 21050157 is 75105012.

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

It is not a de Polignac number, because 21050157 - 2³ = 21050149 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 (21050137) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 184594 + ... + 184707.

It is an arithmetic number, because the mean of its divisors is an integer number (3693020).

Almost surely, 2^21050157 is an apocalyptic number.

It is an amenable number.

21050157 is a deficient number, since it is larger than the sum of its proper divisors (8494003).

21050157 is a wasteful number, since it uses less digits than its factorization.

21050157 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 369323.

The product of its (nonzero) digits is 350, while the sum is 21.

The square root of 21050157 is about 4588.0450084976. The cubic root of 21050157 is about 276.1118927748. Note that the first 3 decimals are identical.

Adding to 21050157 its reverse (75105012), we get a palindrome (96155169).

The spelling of 21050157 in words is "twenty-one million, fifty thousand, one hundred fifty-seven".