61913971 has 4 divisors (see below), whose sum is σ = 70758832. Its totient is φ = 53069112.

The previous prime is 61913947. The next prime is 61914019. The reversal of 61913971 is 17931916.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 61913971 - 2²¹ = 59816819 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 61913971.

It is not an unprimeable number, because it can be changed into a prime (61913921) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4422420 + ... + 4422433.

It is an arithmetic number, because the mean of its divisors is an integer number (17689708).

Almost surely, 2^61913971 is an apocalyptic number.

61913971 is a deficient number, since it is larger than the sum of its proper divisors (8844861).

61913971 is an equidigital number, since it uses as much as digits as its factorization.

61913971 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8844860.

The product of its digits is 10206, while the sum is 37.

The square root of 61913971 is about 7868.5431307199. The cubic root of 61913971 is about 395.6060152345.

The spelling of 61913971 in words is "sixty-one million, nine hundred thirteen thousand, nine hundred seventy-one".