61298721 has 48 divisors (see below), whose sum is σ = 103420800. Its totient is φ = 35814240.

The previous prime is 61298711. The next prime is 61298759. The reversal of 61298721 is 12789216.

It is not a de Polignac number, because 61298721 - 2⁵ = 61298689 is a prime.

It is an alternating number because its digits alternate between even and odd.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61298711) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 94420 + ... + 95066.

It is an arithmetic number, because the mean of its divisors is an integer number (2154600).

Almost surely, 2^61298721 is an apocalyptic number.

It is an amenable number.

61298721 is a deficient number, since it is larger than the sum of its proper divisors (42122079).

61298721 is a wasteful number, since it uses less digits than its factorization.

61298721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 707 (or 690 counting only the distinct ones).

The product of its digits is 12096, while the sum is 36.

The square root of 61298721 is about 7829.3499730182. The cubic root of 61298721 is about 394.2912484033.

The spelling of 61298721 in words is "sixty-one million, two hundred ninety-eight thousand, seven hundred twenty-one".