61994821 has 16 divisors (see below), whose sum is σ = 74188800. Its totient is φ = 50651568.

The previous prime is 61994797. The next prime is 61994839. The reversal of 61994821 is 12849916.

It is a cyclic number.

It is not a de Polignac number, because 61994821 - 2¹¹ = 61992773 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61997821) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 67000 + ... + 67918.

It is an arithmetic number, because the mean of its divisors is an integer number (4636800).

Almost surely, 2^61994821 is an apocalyptic number.

It is an amenable number.

61994821 is a deficient number, since it is larger than the sum of its proper divisors (12193979).

61994821 is a wasteful number, since it uses less digits than its factorization.

61994821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1368.

The product of its digits is 31104, while the sum is 40.

The square root of 61994821 is about 7873.6790003149. The cubic root of 61994821 is about 395.7781402737.

The spelling of 61994821 in words is "sixty-one million, nine hundred ninety-four thousand, eight hundred twenty-one".