61290815 has 4 divisors (see below), whose sum is σ = 73548984. Its totient is φ = 49032648.

The previous prime is 61290811. The next prime is 61290847. The reversal of 61290815 is 51809216.

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 61290815 - 2² = 61290811 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61290811) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6129077 + ... + 6129086.

It is an arithmetic number, because the mean of its divisors is an integer number (18387246).

Almost surely, 2^61290815 is an apocalyptic number.

61290815 is a deficient number, since it is larger than the sum of its proper divisors (12258169).

61290815 is a wasteful number, since it uses less digits than its factorization.

61290815 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12258168.

The product of its (nonzero) digits is 4320, while the sum is 32.

The square root of 61290815 is about 7828.8450616933. The cubic root of 61290815 is about 394.2742964420.

The spelling of 61290815 in words is "sixty-one million, two hundred ninety thousand, eight hundred fifteen".