551613645 has 96 divisors (see below), whose sum is σ = 1092873600. Its totient is φ = 264695040.

The previous prime is 551613641. The next prime is 551613653. The reversal of 551613645 is 546316155.

551613645 is a `hidden beast` number, since 5 + 5 + 1 + 6 + 1 + 3 + 645 = 666.

It is not a de Polignac number, because 551613645 - 2² = 551613641 is a prime.

It is a super-3 number, since 3×551613645³ (a number of 27 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (551613641) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 1991247 + ... + 1991523.

It is an arithmetic number, because the mean of its divisors is an integer number (11384100).

Almost surely, 2^551613645 is an apocalyptic number.

551613645 is a gapful number since it is divisible by the number (55) formed by its first and last digit.

It is an amenable number.

551613645 is a deficient number, since it is larger than the sum of its proper divisors (541259955).

551613645 is a wasteful number, since it uses less digits than its factorization.

551613645 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 457 (or 445 counting only the distinct ones).

The product of its digits is 54000, while the sum is 36.

The square root of 551613645 is about 23486.4566293002. The cubic root of 551613645 is about 820.1217571531.

It can be divided in two parts, 5516136 and 45, that added together give a triangular number (5516181 = T₃₃₂₁).

The spelling of 551613645 in words is "five hundred fifty-one million, six hundred thirteen thousand, six hundred forty-five".