21122040 has 32 divisors (see below), whose sum is σ = 63366480. Its totient is φ = 5632512.

The previous prime is 21122033. The next prime is 21122069. The reversal of 21122040 is 4022112.

It is a super-2 number, since 2×21122040² = 892281147523200, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (12).

It is a congruent number.

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, 87889 + ... + 88128.

Almost surely, 2^21122040 is an apocalyptic number.

21122040 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21122040 is an abundant number, since it is smaller than the sum of its proper divisors (42244440).

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

21122040 is a wasteful number, since it uses less digits than its factorization.

21122040 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 176031 (or 176027 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 12.

The square root of 21122040 is about 4595.8720608825. The cubic root of 21122040 is about 276.4258287014.

Adding to 21122040 its reverse (4022112), we get a palindrome (25144152).

The spelling of 21122040 in words is "twenty-one million, one hundred twenty-two thousand, forty".