551620440 has 144 divisors (see below), whose sum is σ = 2085529680. Its totient is φ = 126080640.

The previous prime is 551620439. The next prime is 551620493. The reversal of 551620440 is 44026155.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 2005 + ... + 33275.

It is an arithmetic number, because the mean of its divisors is an integer number (14482845).

Almost surely, 2^551620440 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 551620440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1042764840).

551620440 is an abundant number, since it is smaller than the sum of its proper divisors (1533909240).

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

551620440 is a wasteful number, since it uses less digits than its factorization.

551620440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 31302 (or 31288 counting only the distinct ones).

The product of its (nonzero) digits is 4800, while the sum is 27.

The square root of 551620440 is about 23486.6012866911. The cubic root of 551620440 is about 820.1251246698.

Adding to 551620440 its reverse (44026155), we get a palindrome (595646595).

The spelling of 551620440 in words is "five hundred fifty-one million, six hundred twenty thousand, four hundred forty".