21122113640 has 32 divisors (see below), whose sum is σ = 47554658280. Its totient is φ = 8443529472.

The previous prime is 21122113637. The next prime is 21122113729. The reversal of 21122113640 is 4631122112.

It can be written as a sum of positive squares in 4 ways, for example, as 14538089476 + 6584024164 = 120574^2 + 81142^2 .

It is a super-2 number, since 2×21122113640² (a number of 21 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 101447 + ... + 229206.

Almost surely, 2^21122113640 is an apocalyptic number.

21122113640 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21122113640 is an abundant number, since it is smaller than the sum of its proper divisors (26432544640).

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

21122113640 is a wasteful number, since it uses less digits than its factorization.

21122113640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 332261 (or 332257 counting only the distinct ones).

The product of its (nonzero) digits is 576, while the sum is 23.

Adding to 21122113640 its reverse (4631122112), we get a palindrome (25753235752).

The spelling of 21122113640 in words is "twenty-one billion, one hundred twenty-two million, one hundred thirteen thousand, six hundred forty".