21050402 has 8 divisors (see below), whose sum is σ = 31605276. Its totient is φ = 10515312.

The previous prime is 21050401. The next prime is 21050413. The reversal of 21050402 is 20405012.

It can be written as a sum of positive squares in 2 ways, for example, as 17631601 + 3418801 = 4199^2 + 1849^2 .

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

It is not an unprimeable number, because it can be changed into a prime (21050401) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1913 + ... + 6764.

Almost surely, 2^21050402 is an apocalyptic number.

21050402 is a deficient number, since it is larger than the sum of its proper divisors (10554874).

21050402 is a wasteful number, since it uses less digits than its factorization.

21050402 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9892.

The product of its (nonzero) digits is 80, while the sum is 14.

The square root of 21050402 is about 4588.0717082452. The cubic root of 21050402 is about 276.1129639806.

Adding to 21050402 its reverse (20405012), we get a palindrome (41455414).

The spelling of 21050402 in words is "twenty-one million, fifty thousand, four hundred two".