2129821551 has 144 divisors (see below), whose sum is σ = 3941124096. Its totient is φ = 1097712000.

The previous prime is 2129821541. The next prime is 2129821559. The reversal of 2129821551 is 1551289212.

2129821551 is a `hidden beast` number, since 2 + 1 + 29 + 82 + 1 + 551 = 666.

It is not a de Polignac number, because 2129821551 - 2⁷ = 2129821423 is a prime.

It is a super-2 number, since 2×2129821551² = 9072279678208091202, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2129821559) by changing a digit.

It is a polite number, since it can be written in 143 ways as a sum of consecutive naturals, for example, 10093836 + ... + 10094046.

Almost surely, 2^2129821551 is an apocalyptic number.

2129821551 is a deficient number, since it is larger than the sum of its proper divisors (1811302545).

2129821551 is a wasteful number, since it uses less digits than its factorization.

2129821551 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 306 (or 292 counting only the distinct ones).

The product of its digits is 14400, while the sum is 36.

The square root of 2129821551 is about 46149.9897183087. The cubic root of 2129821551 is about 1286.6124189039.

It can be divided in two parts, 21298 and 21551, that added together give a square (42849 = 207²).

The spelling of 2129821551 in words is "two billion, one hundred twenty-nine million, eight hundred twenty-one thousand, five hundred fifty-one".