20077440 has 64 divisors (see below), whose sum is σ = 64002960. Its totient is φ = 5353472.

The previous prime is 20077439. The next prime is 20077489. The reversal of 20077440 is 4477002.

It is a tau number, because it is divible by the number of its divisors (64).

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a self number, because there is not a number n which added to its sum of digits gives 20077440.

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, 3309 + ... + 7148.

Almost surely, 2^20077440 is an apocalyptic number.

20077440 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20077440 is an abundant number, since it is smaller than the sum of its proper divisors (43925520).

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

20077440 is a wasteful number, since it uses less digits than its factorization.

20077440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10479 (or 10467 counting only the distinct ones).

The product of its (nonzero) digits is 1568, while the sum is 24.

The square root of 20077440 is about 4480.7856453975. The cubic root of 20077440 is about 271.7916512901.

The spelling of 20077440 in words is "twenty million, seventy-seven thousand, four hundred forty".