2616250781 has 4 divisors (see below), whose sum is σ = 2625561564. Its totient is φ = 2606940000.

The previous prime is 2616250753. The next prime is 2616250789. The reversal of 2616250781 is 1870526162.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1870526162 = 2 ⋅935263081.

It can be written as a sum of positive squares in 2 ways, for example, as 1669457881 + 946792900 = 40859^2 + 30770^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2616250781 is a prime.

It is a super-2 number, since 2×2616250781² = 13689536298166219922, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2616250789) 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, 4654970 + ... + 4655531.

It is an arithmetic number, because the mean of its divisors is an integer number (656390391).

Almost surely, 2^2616250781 is an apocalyptic number.

It is an amenable number.

2616250781 is a deficient number, since it is larger than the sum of its proper divisors (9310783).

2616250781 is an equidigital number, since it uses as much as digits as its factorization.

2616250781 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9310782.

The product of its (nonzero) digits is 40320, while the sum is 38.

The square root of 2616250781 is about 51149.2989297019. The cubic root of 2616250781 is about 1377.9277834491.

The spelling of 2616250781 in words is "two billion, six hundred sixteen million, two hundred fifty thousand, seven hundred eighty-one".