2501981 has 8 divisors (see below), whose sum is σ = 2570400. Its totient is φ = 2434608.

The previous prime is 2501959. The next prime is 2501987. The reversal of 2501981 is 1891052.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 2501981 - 2¹⁰ = 2500957 is a prime.

It is a super-2 number, since 2×2501981² = 12519817848722, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 2501981.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2501987) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 6995 + ... + 7343.

It is an arithmetic number, because the mean of its divisors is an integer number (321300).

2^2501981 is an apocalyptic number.

It is an amenable number.

2501981 is a deficient number, since it is larger than the sum of its proper divisors (68419).

2501981 is a wasteful number, since it uses less digits than its factorization.

2501981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 523.

The product of its (nonzero) digits is 720, while the sum is 26.

The square root of 2501981 is about 1581.7651532386. The cubic root of 2501981 is about 135.7567197738.

The spelling of 2501981 in words is "two million, five hundred one thousand, nine hundred eighty-one".