4001321537 has 2 divisors, whose sum is σ = 4001321538. Its totient is φ = 4001321536.

The previous prime is 4001321507. The next prime is 4001321557. The reversal of 4001321537 is 7351231004.

It is a Cunningham number, because it is equal to 63256²+1.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 4001321536 + 1 = 63256^2 + 1^2 .

It is a cyclic number.

It is not a de Polignac number, because 4001321537 - 2¹⁶ = 4001256001 is a prime.

It is not a weakly prime, because it can be changed into another prime (4001321507) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2000660768 + 2000660769.

It is an arithmetic number, because the mean of its divisors is an integer number (2000660769).

Almost surely, 2^4001321537 is an apocalyptic number.

It is an amenable number.

4001321537 is a deficient number, since it is larger than the sum of its proper divisors (1).

4001321537 is an equidigital number, since it uses as much as digits as its factorization.

4001321537 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2520, while the sum is 26.

The square root of 4001321537 is about 63256.0000079044. Note that the first 5 decimals coincide. The cubic root of 4001321537 is about 1587.5758501548.

The spelling of 4001321537 in words is "four billion, one million, three hundred twenty-one thousand, five hundred thirty-seven".