2491501861 has 8 divisors (see below), whose sum is σ = 2655768600. Its totient is φ = 2329202688.

The previous prime is 2491501847. The next prime is 2491501877. The reversal of 2491501861 is 1681051942.

It can be written as a sum of positive squares in 4 ways, for example, as 893025 + 2490608836 = 945^2 + 49906^2 .

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 2491501861 - 2¹⁷ = 2491370789 is a prime.

It is a super-3 number, since 3×2491501861³ (a number of 29 digits) contains 333 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 2491501861.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2491501801) 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, 489276 + ... + 494341.

It is an arithmetic number, because the mean of its divisors is an integer number (331971075).

Almost surely, 2^2491501861 is an apocalyptic number.

It is an amenable number.

2491501861 is a deficient number, since it is larger than the sum of its proper divisors (164266739).

2491501861 is a wasteful number, since it uses less digits than its factorization.

2491501861 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 983783.

The product of its (nonzero) digits is 17280, while the sum is 37.

The square root of 2491501861 is about 49914.9462686278. The cubic root of 2491501861 is about 1355.6692292893.

The spelling of 2491501861 in words is "two billion, four hundred ninety-one million, five hundred one thousand, eight hundred sixty-one".