61920661 has 12 divisors (see below), whose sum is σ = 68253472. Its totient is φ = 56133000.

The previous prime is 61920659. The next prime is 61920689. The reversal of 61920661 is 16602916.

It is not a de Polignac number, because 61920661 - 2¹ = 61920659 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61920161) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 75946 + ... + 76756.

Almost surely, 2^61920661 is an apocalyptic number.

It is an amenable number.

61920661 is a deficient number, since it is larger than the sum of its proper divisors (6332811).

61920661 is a wasteful number, since it uses less digits than its factorization.

61920661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1464 (or 1453 counting only the distinct ones).

The product of its (nonzero) digits is 3888, while the sum is 31.

The square root of 61920661 is about 7868.9682296982. The cubic root of 61920661 is about 395.6202635476.

The spelling of 61920661 in words is "sixty-one million, nine hundred twenty thousand, six hundred sixty-one".