2051551 has 4 divisors (see below), whose sum is σ = 2077600. Its totient is φ = 2025504.

The previous prime is 2051537. The next prime is 2051587. The reversal of 2051551 is 1551502.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2051551 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2051051) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 12906 + ... + 13063.

It is an arithmetic number, because the mean of its divisors is an integer number (519400).

2^2051551 is an apocalyptic number.

2051551 is a deficient number, since it is larger than the sum of its proper divisors (26049).

2051551 is an equidigital number, since it uses as much as digits as its factorization.

2051551 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 26048.

The product of its (nonzero) digits is 250, while the sum is 19.

The square root of 2051551 is about 1432.3236366129. The cubic root of 2051551 is about 127.0654384072.

The spelling of 2051551 in words is "two million, fifty-one thousand, five hundred fifty-one".