2621655749 has 2 divisors, whose sum is σ = 2621655750. Its totient is φ = 2621655748.

The previous prime is 2621655727. The next prime is 2621655779. The reversal of 2621655749 is 9475561262.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 2609370724 + 12285025 = 51082^2 + 3505^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2621655749 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2621655779) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1310827874 + 1310827875.

It is an arithmetic number, because the mean of its divisors is an integer number (1310827875).

Almost surely, 2^2621655749 is an apocalyptic number.

It is an amenable number.

2621655749 is a deficient number, since it is larger than the sum of its proper divisors (1).

2621655749 is an equidigital number, since it uses as much as digits as its factorization.

2621655749 is an evil number, because the sum of its binary digits is even.

The product of its digits is 907200, while the sum is 47.

The square root of 2621655749 is about 51202.1068804790. The cubic root of 2621655749 is about 1378.8760274976.

The spelling of 2621655749 in words is "two billion, six hundred twenty-one million, six hundred fifty-five thousand, seven hundred forty-nine".