61445999 has 4 divisors (see below), whose sum is σ = 63428160. Its totient is φ = 59463840.

The previous prime is 61445957. The next prime is 61446013. The reversal of 61445999 is 99954416.

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 61445999 - 2¹⁶ = 61380463 is a prime.

It is a super-2 number, since 2×61445999² = 7551221586216002, 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 (61445929) 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, 991034 + ... + 991095.

It is an arithmetic number, because the mean of its divisors is an integer number (15857040).

Almost surely, 2^61445999 is an apocalyptic number.

61445999 is a deficient number, since it is larger than the sum of its proper divisors (1982161).

61445999 is a wasteful number, since it uses less digits than its factorization.

61445999 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1982160.

The product of its digits is 349920, while the sum is 47.

The square root of 61445999 is about 7838.7498365492. The cubic root of 61445999 is about 394.6067741887.

The spelling of 61445999 in words is "sixty-one million, four hundred forty-five thousand, nine hundred ninety-nine".