21210431402 has 8 divisors (see below), whose sum is σ = 31858469856. Its totient is φ = 10590941452.

The previous prime is 21210431399. The next prime is 21210431419. The reversal of 21210431402 is 20413401212.

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

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7135268 + ... + 7138239.

It is an arithmetic number, because the mean of its divisors is an integer number (3982308732).

Almost surely, 2^21210431402 is an apocalyptic number.

21210431402 is a deficient number, since it is larger than the sum of its proper divisors (10648038454).

21210431402 is a wasteful number, since it uses less digits than its factorization.

21210431402 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14274252.

The product of its (nonzero) digits is 384, while the sum is 20.

Adding to 21210431402 its reverse (20413401212), we get a palindrome (41623832614).

The spelling of 21210431402 in words is "twenty-one billion, two hundred ten million, four hundred thirty-one thousand, four hundred two".