21013020030 has 32 divisors (see below), whose sum is σ = 50477551488. Its totient is φ = 5598327200.

The previous prime is 21013020029. The next prime is 21013020031. The reversal of 21013020030 is 3002031012.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (21013020029) and next prime (21013020031).

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 21013019988 and 21013020015.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21013020031) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 288276 + ... + 353735.

It is an arithmetic number, because the mean of its divisors is an integer number (1577423484).

Almost surely, 2^21013020030 is an apocalyptic number.

21013020030 is an abundant number, since it is smaller than the sum of its proper divisors (29464531458).

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

21013020030 is a wasteful number, since it uses less digits than its factorization.

21013020030 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 643112.

The product of its (nonzero) digits is 36, while the sum is 12.

Adding to 21013020030 its reverse (3002031012), we get a palindrome (24015051042).

The spelling of 21013020030 in words is "twenty-one billion, thirteen million, twenty thousand, thirty".