661654154 has 12 divisors (see below), whose sum is σ = 1154519154. Its totient is φ = 283566024.

The previous prime is 661654153. The next prime is 661654159. The reversal of 661654154 is 451456166.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 633277225 + 28376929 = 25165^2 + 5327^2 .

It is a super-3 number, since 3×661654154³ (a number of 27 digits) contains 333 as substring.

It is not an unprimeable number, because it can be changed into a prime (661654153) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 3375689 + ... + 3375884.

Almost surely, 2^661654154 is an apocalyptic number.

661654154 is a deficient number, since it is larger than the sum of its proper divisors (492865000).

661654154 is a wasteful number, since it uses less digits than its factorization.

661654154 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6751589 (or 6751582 counting only the distinct ones).

The product of its digits is 86400, while the sum is 38.

The square root of 661654154 is about 25722.6389392690. The cubic root of 661654154 is about 871.3855378885.

The spelling of 661654154 in words is "six hundred sixty-one million, six hundred fifty-four thousand, one hundred fifty-four".