20101440 has 56 divisors (see below), whose sum is σ = 63825120. Its totient is φ = 5360128.

The previous prime is 20101427. The next prime is 20101483. The reversal of 20101440 is 4410102.

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, 9510 + ... + 11429.

Almost surely, 2^20101440 is an apocalyptic number.

20101440 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20101440 is an abundant number, since it is smaller than the sum of its proper divisors (43723680).

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

20101440 is a wasteful number, since it uses less digits than its factorization.

20101440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20959 (or 20949 counting only the distinct ones).

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

The square root of 20101440 is about 4483.4629473210. The cubic root of 20101440 is about 271.8999055002.

Adding to 20101440 its reverse (4410102), we get a palindrome (24511542).

The spelling of 20101440 in words is "twenty million, one hundred one thousand, four hundred forty".