21511202046 has 16 divisors (see below), whose sum is σ = 43074310800. Its totient is φ = 7161749568.

The previous prime is 21511202021. The next prime is 21511202057. The reversal of 21511202046 is 64020211512.

It is a super-2 number, since 2×21511202046² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

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 7 ways as a sum of consecutive naturals, for example, 2157391 + ... + 2167338.

It is an arithmetic number, because the mean of its divisors is an integer number (2692144425).

Almost surely, 2^21511202046 is an apocalyptic number.

21511202046 is an abundant number, since it is smaller than the sum of its proper divisors (21563108754).

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

21511202046 is a wasteful number, since it uses less digits than its factorization.

21511202046 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4325563.

The product of its (nonzero) digits is 960, while the sum is 24.

Adding to 21511202046 its reverse (64020211512), we get a palindrome (85531413558).

The spelling of 21511202046 in words is "twenty-one billion, five hundred eleven million, two hundred two thousand, forty-six".