61813907 has 4 divisors (see below), whose sum is σ = 63807936. Its totient is φ = 59819880.

The previous prime is 61813901. The next prime is 61813909. The reversal of 61813907 is 70931816.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-61813907 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (61813901) 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, 996968 + ... + 997029.

It is an arithmetic number, because the mean of its divisors is an integer number (15951984).

Almost surely, 2^61813907 is an apocalyptic number.

61813907 is a deficient number, since it is larger than the sum of its proper divisors (1994029).

61813907 is a wasteful number, since it uses less digits than its factorization.

61813907 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1994028.

The product of its (nonzero) digits is 9072, while the sum is 35.

The square root of 61813907 is about 7862.1820762432. The cubic root of 61813907 is about 395.3927770655.

The spelling of 61813907 in words is "sixty-one million, eight hundred thirteen thousand, nine hundred seven".