61521207 has 16 divisors (see below), whose sum is σ = 89672832. Its totient is φ = 37207520.

The previous prime is 61521203. The next prime is 61521233. The reversal of 61521207 is 70212516.

It is a cyclic number.

It is not a de Polignac number, because 61521207 - 2² = 61521203 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61521203) 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 15 ways as a sum of consecutive naturals, for example, 16708 + ... + 20054.

It is an arithmetic number, because the mean of its divisors is an integer number (5604552).

Almost surely, 2^61521207 is an apocalyptic number.

61521207 is a deficient number, since it is larger than the sum of its proper divisors (28151625).

61521207 is a wasteful number, since it uses less digits than its factorization.

61521207 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3918.

The product of its (nonzero) digits is 840, while the sum is 24.

The square root of 61521207 is about 7843.5455630729. The cubic root of 61521207 is about 394.7677040394.

The spelling of 61521207 in words is "sixty-one million, five hundred twenty-one thousand, two hundred seven".