661420895 has 8 divisors (see below), whose sum is σ = 810592704. Its totient is φ = 517878304.

The previous prime is 661420831. The next prime is 661420909. The reversal of 661420895 is 598024166.

It is a happy number.

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 661420895 - 2⁶ = 661420831 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1407044 + ... + 1407513.

It is an arithmetic number, because the mean of its divisors is an integer number (101324088).

Almost surely, 2^661420895 is an apocalyptic number.

661420895 is a deficient number, since it is larger than the sum of its proper divisors (149171809).

661420895 is a wasteful number, since it uses less digits than its factorization.

661420895 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2814609.

The product of its (nonzero) digits is 103680, while the sum is 41.

The square root of 661420895 is about 25718.1044208161. The cubic root of 661420895 is about 871.2831266776.

The spelling of 661420895 in words is "six hundred sixty-one million, four hundred twenty thousand, eight hundred ninety-five".