61931537 has 2 divisors, whose sum is σ = 61931538. Its totient is φ = 61931536.

The previous prime is 61931491. The next prime is 61931539. The reversal of 61931537 is 73513916.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 54700816 + 7230721 = 7396^2 + 2689^2 .

It is a cyclic number.

It is not a de Polignac number, because 61931537 - 2²⁰ = 60882961 is a prime.

Together with 61931539, it forms a pair of twin primes.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 61931497 and 61931506.

It is not a weakly prime, because it can be changed into another prime (61931539) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 30965768 + 30965769.

It is an arithmetic number, because the mean of its divisors is an integer number (30965769).

Almost surely, 2^61931537 is an apocalyptic number.

It is an amenable number.

61931537 is a deficient number, since it is larger than the sum of its proper divisors (1).

61931537 is an equidigital number, since it uses as much as digits as its factorization.

61931537 is an evil number, because the sum of its binary digits is even.

The product of its digits is 17010, while the sum is 35.

The square root of 61931537 is about 7869.6592683546. The cubic root of 61931537 is about 395.6434249826.

The spelling of 61931537 in words is "sixty-one million, nine hundred thirty-one thousand, five hundred thirty-seven".