21010213434 has 48 divisors (see below), whose sum is σ = 48897813888. Its totient is φ = 6000841728.

The previous prime is 21010213423. The next prime is 21010213481. The reversal of 21010213434 is 43431201012.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is a self number, because there is not a number n which added to its sum of digits gives 21010213434.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 972154 + ... + 993530.

It is an arithmetic number, because the mean of its divisors is an integer number (1018704456).

Almost surely, 2^21010213434 is an apocalyptic number.

21010213434 is an abundant number, since it is smaller than the sum of its proper divisors (27887600454).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21010213434 is a wasteful number, since it uses less digits than its factorization.

21010213434 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 24739 (or 24732 counting only the distinct ones).

The product of its (nonzero) digits is 576, while the sum is 21.

Adding to 21010213434 its reverse (43431201012), we get a palindrome (64441414446).

The spelling of 21010213434 in words is "twenty-one billion, ten million, two hundred thirteen thousand, four hundred thirty-four".