3662621581 has 2 divisors, whose sum is σ = 3662621582. Its totient is φ = 3662621580.

The previous prime is 3662621563. The next prime is 3662621587. The reversal of 3662621581 is 1851262663.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 2607021481 + 1055600100 = 51059^2 + 32490^2 .

It is a cyclic number.

It is not a de Polignac number, because 3662621581 - 2¹⁷ = 3662490509 is a prime.

It is a super-2 number, since 2×3662621581² = 26829593691213879122, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (3662621587) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1831310790 + 1831310791.

It is an arithmetic number, because the mean of its divisors is an integer number (1831310791).

Almost surely, 2^3662621581 is an apocalyptic number.

It is an amenable number.

3662621581 is a deficient number, since it is larger than the sum of its proper divisors (1).

3662621581 is an equidigital number, since it uses as much as digits as its factorization.

3662621581 is an evil number, because the sum of its binary digits is even.

The product of its digits is 103680, while the sum is 40.

The square root of 3662621581 is about 60519.5966691782. The cubic root of 3662621581 is about 1541.4544056413.

The spelling of 3662621581 in words is "three billion, six hundred sixty-two million, six hundred twenty-one thousand, five hundred eighty-one".