61996981 has 8 divisors (see below), whose sum is σ = 65378720. Its totient is φ = 58627152.

The previous prime is 61996973. The next prime is 61996999. The reversal of 61996981 is 18969916.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 61996981 - 2³ = 61996973 is a prime.

It is a super-2 number, since 2×61996981² = 7687251306228722, 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 (61996951) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 8986 + ... + 14308.

It is an arithmetic number, because the mean of its divisors is an integer number (8172340).

Almost surely, 2^61996981 is an apocalyptic number.

It is an amenable number.

61996981 is a deficient number, since it is larger than the sum of its proper divisors (3381739).

61996981 is a wasteful number, since it uses less digits than its factorization.

61996981 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5955.

The product of its digits is 209952, while the sum is 49.

The square root of 61996981 is about 7873.8161649863. The cubic root of 61996981 is about 395.7827367375.

The spelling of 61996981 in words is "sixty-one million, nine hundred ninety-six thousand, nine hundred eighty-one".