661504045 has 32 divisors (see below), whose sum is σ = 841446144. Its totient is φ = 498624000.

The previous prime is 661504043. The next prime is 661504073. The reversal of 661504045 is 540405166.

661504045 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 661504045 - 2¹ = 661504043 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 661503998 and 661504016.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (661504043) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 889944 + ... + 890686.

It is an arithmetic number, because the mean of its divisors is an integer number (26295192).

Almost surely, 2^661504045 is an apocalyptic number.

It is an amenable number.

661504045 is a deficient number, since it is larger than the sum of its proper divisors (179942099).

661504045 is a wasteful number, since it uses less digits than its factorization.

661504045 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 933.

The product of its (nonzero) digits is 14400, while the sum is 31.

The square root of 661504045 is about 25719.7209355001. The cubic root of 661504045 is about 871.3196360353.

The spelling of 661504045 in words is "six hundred sixty-one million, five hundred four thousand, forty-five".