2515421 has 4 divisors (see below), whose sum is σ = 2518812. Its totient is φ = 2512032.

The previous prime is 2515417. The next prime is 2515427. The reversal of 2515421 is 1245152.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 722500 + 1792921 = 850^2 + 1339^2 .

It is a cyclic number.

It is not a de Polignac number, because 2515421 - 2² = 2515417 is a prime.

It is an Ulam number.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 2515393 and 2515402.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2515427) 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, 50 + ... + 2243.

It is an arithmetic number, because the mean of its divisors is an integer number (629703).

2^2515421 is an apocalyptic number.

It is an amenable number.

2515421 is a deficient number, since it is larger than the sum of its proper divisors (3391).

2515421 is a wasteful number, since it uses less digits than its factorization.

2515421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3390.

The product of its digits is 400, while the sum is 20.

The square root of 2515421 is about 1586.0078814432. The cubic root of 2515421 is about 135.9993692301. Note that the first 3 decimals are identical.

The spelling of 2515421 in words is "two million, five hundred fifteen thousand, four hundred twenty-one".