551720155 has 24 divisors (see below), whose sum is σ = 771190848. Its totient is φ = 377814528.

The previous prime is 551720153. The next prime is 551720179. The reversal of 551720155 is 551027155.

It is not a de Polignac number, because 551720155 - 2¹ = 551720153 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (551720153) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 324267 + ... + 325963.

It is an arithmetic number, because the mean of its divisors is an integer number (32132952).

Almost surely, 2^551720155 is an apocalyptic number.

551720155 is a deficient number, since it is larger than the sum of its proper divisors (219470693).

551720155 is a wasteful number, since it uses less digits than its factorization.

551720155 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3043 (or 3036 counting only the distinct ones).

The product of its (nonzero) digits is 8750, while the sum is 31.

The square root of 551720155 is about 23488.7239968458. The cubic root of 551720155 is about 820.1745389915.

The spelling of 551720155 in words is "five hundred fifty-one million, seven hundred twenty thousand, one hundred fifty-five".