661010157 has 6 divisors (see below), whose sum is σ = 954792462. Its totient is φ = 440673432.

The previous prime is 661010131. The next prime is 661010173. The reversal of 661010157 is 751010166.

It can be written as a sum of positive squares in only one way, i.e., 653006916 + 8003241 = 25554^2 + 2829^2 .

It is not a de Polignac number, because 661010157 - 2⁷ = 661010029 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 661010157.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (661017157) 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, 36722778 + ... + 36722795.

It is an arithmetic number, because the mean of its divisors is an integer number (159132077).

Almost surely, 2^661010157 is an apocalyptic number.

It is an amenable number.

661010157 is a deficient number, since it is larger than the sum of its proper divisors (293782305).

661010157 is a wasteful number, since it uses less digits than its factorization.

661010157 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 73445579 (or 73445576 counting only the distinct ones).

The product of its (nonzero) digits is 1260, while the sum is 27.

The square root of 661010157 is about 25710.1177943626. The cubic root of 661010157 is about 871.1027356460.

Subtracting 661010157 from its reverse (751010166), we obtain a palindrome (90000009).

The spelling of 661010157 in words is "six hundred sixty-one million, ten thousand, one hundred fifty-seven".