61638371 has 2 divisors, whose sum is σ = 61638372. Its totient is φ = 61638370.

The previous prime is 61638361. The next prime is 61638383. The reversal of 61638371 is 17383616.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 61638371 - 2²² = 57444067 is a prime.

It is not a weakly prime, because it can be changed into another prime (61638331) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 30819185 + 30819186.

It is an arithmetic number, because the mean of its divisors is an integer number (30819186).

Almost surely, 2^61638371 is an apocalyptic number.

61638371 is a deficient number, since it is larger than the sum of its proper divisors (1).

61638371 is an equidigital number, since it uses as much as digits as its factorization.

61638371 is an evil number, because the sum of its binary digits is even.

The product of its digits is 18144, while the sum is 35.

The square root of 61638371 is about 7851.0108266388. The cubic root of 61638371 is about 395.0181501033.

The spelling of 61638371 in words is "sixty-one million, six hundred thirty-eight thousand, three hundred seventy-one".