2551515421 has 16 divisors (see below), whose sum is σ = 3143588224. Its totient is φ = 2016684864.

The previous prime is 2551515413. The next prime is 2551515433. The reversal of 2551515421 is 1245151552.

It is a cyclic number.

It is not a de Polignac number, because 2551515421 - 2³ = 2551515413 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2551515521) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 76666 + ... + 104788.

It is an arithmetic number, because the mean of its divisors is an integer number (196474264).

Almost surely, 2^2551515421 is an apocalyptic number.

It is an amenable number.

2551515421 is a deficient number, since it is larger than the sum of its proper divisors (592072803).

2551515421 is a wasteful number, since it uses less digits than its factorization.

2551515421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 29140.

The product of its digits is 10000, while the sum is 31.

The square root of 2551515421 is about 50512.5273669810. The cubic root of 2551515421 is about 1366.4677902626.

Adding to 2551515421 its reverse (1245151552), we get a palindrome (3796666973).

The spelling of 2551515421 in words is "two billion, five hundred fifty-one million, five hundred fifteen thousand, four hundred twenty-one".