21035210402 has 4 divisors (see below), whose sum is σ = 31552815606. Its totient is φ = 10517605200.

The previous prime is 21035210323. The next prime is 21035210419. The reversal of 21035210402 is 20401253012.

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

It can be written as a sum of positive squares in only one way, i.e., 17190094321 + 3845116081 = 131111^2 + 62009^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5258802599 + ... + 5258802602.

Almost surely, 2^21035210402 is an apocalyptic number.

21035210402 is a deficient number, since it is larger than the sum of its proper divisors (10517605204).

21035210402 is a wasteful number, since it uses less digits than its factorization.

21035210402 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10517605203.

The product of its (nonzero) digits is 480, while the sum is 20.

Adding to 21035210402 its reverse (20401253012), we get a palindrome (41436463414).

The spelling of 21035210402 in words is "twenty-one billion, thirty-five million, two hundred ten thousand, four hundred two".