661012502 has 16 divisors (see below), whose sum is σ = 1054153440. Its totient is φ = 310170432.

The previous prime is 661012501. The next prime is 661012519. The reversal of 661012502 is 205210166.

It is a Harshad number since it is a multiple of its sum of digits (23).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (661012501) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 133127 + ... + 138002.

It is an arithmetic number, because the mean of its divisors is an integer number (65884590).

Almost surely, 2^661012502 is an apocalyptic number.

661012502 is a deficient number, since it is larger than the sum of its proper divisors (393140938).

661012502 is a wasteful number, since it uses less digits than its factorization.

661012502 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 271207.

The product of its (nonzero) digits is 720, while the sum is 23.

The square root of 661012502 is about 25710.1633989362. The cubic root of 661012502 is about 871.1037657530.

Adding to 661012502 its reverse (205210166), we get a palindrome (866222668).

The spelling of 661012502 in words is "six hundred sixty-one million, twelve thousand, five hundred two".