67561537 has 2 divisors, whose sum is σ = 67561538. Its totient is φ = 67561536.

The previous prime is 67561531. The next prime is 67561577. The reversal of 67561537 is 73516576.

It is a happy number.

It is an a-pointer prime, because the next prime (67561577) can be obtained adding 67561537 to its sum of digits (40).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 46022656 + 21538881 = 6784^2 + 4641^2 .

It is a cyclic number.

It is not a de Polignac number, because 67561537 - 2⁷ = 67561409 is a prime.

It is a super-2 number, since 2×67561537² = 9129122563604738, which contains 22 as substring.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 67561537.

It is not a weakly prime, because it can be changed into another prime (67561531) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33780768 + 33780769.

It is an arithmetic number, because the mean of its divisors is an integer number (33780769).

Almost surely, 2^67561537 is an apocalyptic number.

It is an amenable number.

67561537 is a deficient number, since it is larger than the sum of its proper divisors (1).

67561537 is an equidigital number, since it uses as much as digits as its factorization.

67561537 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 132300, while the sum is 40.

The square root of 67561537 is about 8219.5825319781. The cubic root of 67561537 is about 407.2863361057.

The spelling of 67561537 in words is "sixty-seven million, five hundred sixty-one thousand, five hundred thirty-seven".