55219440 has 40 divisors (see below), whose sum is σ = 171181008. Its totient is φ = 14725120.

The previous prime is 55219403. The next prime is 55219447. The reversal of 55219440 is 4491255.

It is a tau number, because it is divible by the number of its divisors (40).

It is a Smith number, since the sum of its digits (30) coincides with the sum of the digits of its prime factors.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a junction number, because it is equal to n+sod(n) for n = 55219398 and 55219407.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (55219447) 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, 114801 + ... + 115280.

Almost surely, 2^55219440 is an apocalyptic number.

It is an amenable number.

55219440 is an abundant number, since it is smaller than the sum of its proper divisors (115961568).

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

55219440 is a wasteful number, since it uses less digits than its factorization.

55219440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 230097 (or 230091 counting only the distinct ones).

The product of its (nonzero) digits is 7200, while the sum is 30.

The square root of 55219440 is about 7430.9784012605. The cubic root of 55219440 is about 380.8003445493.

The spelling of 55219440 in words is "fifty-five million, two hundred nineteen thousand, four hundred forty".