61915919 has 4 divisors (see below), whose sum is σ = 66678696. Its totient is φ = 57153144.

The previous prime is 61915901. The next prime is 61915939. The reversal of 61915919 is 91951916.

61915919 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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 61915919 - 2⁸ = 61915663 is a prime.

It is a super-2 number, since 2×61915919² = 7667162051229122, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61915939) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2381369 + ... + 2381394.

It is an arithmetic number, because the mean of its divisors is an integer number (16669674).

Almost surely, 2^61915919 is an apocalyptic number.

61915919 is a deficient number, since it is larger than the sum of its proper divisors (4762777).

61915919 is a wasteful number, since it uses less digits than its factorization.

61915919 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4762776.

The product of its digits is 21870, while the sum is 41.

The square root of 61915919 is about 7868.6669137790. Note that the first 3 decimals coincide. The cubic root of 61915919 is about 395.6101641766.

The spelling of 61915919 in words is "sixty-one million, nine hundred fifteen thousand, nine hundred nineteen".