55212540 has 24 divisors (see below), whose sum is σ = 154595280. Its totient is φ = 14723328.

The previous prime is 55212523. The next prime is 55212541. The reversal of 55212540 is 4521255.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 55212540.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (55212541) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 460045 + ... + 460164.

It is an arithmetic number, because the mean of its divisors is an integer number (6441470).

Almost surely, 2^55212540 is an apocalyptic number.

It is an amenable number.

55212540 is an abundant number, since it is smaller than the sum of its proper divisors (99382740).

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

55212540 is a wasteful number, since it uses less digits than its factorization.

55212540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 920221 (or 920219 counting only the distinct ones).

The product of its (nonzero) digits is 2000, while the sum is 24.

The square root of 55212540 is about 7430.5141141108. The cubic root of 55212540 is about 380.7844827934.

Adding to 55212540 its reverse (4521255), we get a palindrome (59733795).

The spelling of 55212540 in words is "fifty-five million, two hundred twelve thousand, five hundred forty".