3996754537621 has 2 divisors, whose sum is σ = 3996754537622. Its totient is φ = 3996754537620.

The previous prime is 3996754537609. The next prime is 3996754537673. The reversal of 3996754537621 is 1267354576993.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 3405261262225 + 591493275396 = 1845335^2 + 769086^2 .

It is a cyclic number.

It is not a de Polignac number, because 3996754537621 - 2⁷ = 3996754537493 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (3996754537121) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1998377268810 + 1998377268811.

It is an arithmetic number, because the mean of its divisors is an integer number (1998377268811).

Almost surely, 2^{3996754537621} is an apocalyptic number.

It is an amenable number.

3996754537621 is a deficient number, since it is larger than the sum of its proper divisors (1).

3996754537621 is an equidigital number, since it uses as much as digits as its factorization.

3996754537621 is an evil number, because the sum of its binary digits is even.

The product of its digits is 257191200, while the sum is 67.

The spelling of 3996754537621 in words is "three trillion, nine hundred ninety-six billion, seven hundred fifty-four million, five hundred thirty-seven thousand, six hundred twenty-one".