4001206136521 has 16 divisors (see below), whose sum is σ = 4594983874560. Its totient is φ = 3445791803280.

The previous prime is 4001206136489. The next prime is 4001206136527. The reversal of 4001206136521 is 1256316021004.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 4001206136521 - 2⁵ = 4001206136489 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (4001206136527) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2658460 + ... + 3881986.

It is an arithmetic number, because the mean of its divisors is an integer number (287186492160).

Almost surely, 2^{4001206136521} is an apocalyptic number.

It is an amenable number.

4001206136521 is a deficient number, since it is larger than the sum of its proper divisors (593777738039).

4001206136521 is a wasteful number, since it uses less digits than its factorization.

4001206136521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1239204.

The product of its (nonzero) digits is 8640, while the sum is 31.

The spelling of 4001206136521 in words is "four trillion, one billion, two hundred six million, one hundred thirty-six thousand, five hundred twenty-one".