61722187 has 2 divisors, whose sum is σ = 61722188. Its totient is φ = 61722186.

The previous prime is 61722173. The next prime is 61722251. The reversal of 61722187 is 78122716.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-61722187 is a prime.

It is not a weakly prime, because it can be changed into another prime (61722107) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 30861093 + 30861094.

It is an arithmetic number, because the mean of its divisors is an integer number (30861094).

Almost surely, 2^61722187 is an apocalyptic number.

61722187 is a deficient number, since it is larger than the sum of its proper divisors (1).

61722187 is an equidigital number, since it uses as much as digits as its factorization.

61722187 is an evil number, because the sum of its binary digits is even.

The product of its digits is 9408, while the sum is 34.

The square root of 61722187 is about 7856.3469246209. The cubic root of 61722187 is about 395.1971178735.

The spelling of 61722187 in words is "sixty-one million, seven hundred twenty-two thousand, one hundred eighty-seven".