661562151 has 4 divisors (see below), whose sum is σ = 882082872. Its totient is φ = 441041432.

The previous prime is 661562137. The next prime is 661562173. The reversal of 661562151 is 151265166.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 661562151 - 2⁷ = 661562023 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (661562131) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 110260356 + ... + 110260361.

It is an arithmetic number, because the mean of its divisors is an integer number (220520718).

Almost surely, 2^661562151 is an apocalyptic number.

661562151 is a deficient number, since it is larger than the sum of its proper divisors (220520721).

661562151 is a wasteful number, since it uses less digits than its factorization.

661562151 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 220520720.

The product of its digits is 10800, while the sum is 33.

The square root of 661562151 is about 25720.8505108210. The cubic root of 661562151 is about 871.3451473011.

The spelling of 661562151 in words is "six hundred sixty-one million, five hundred sixty-two thousand, one hundred fifty-one".