121749156 has 45 divisors (see below), whose sum is σ = 318796401. Its totient is φ = 40516848.

The previous prime is 121749149. The next prime is 121749157. The reversal of 121749156 is 651947121.

The square root of 121749156 is 11034.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 396900 + 121352256 = 630^2 + 11016^2 .

It is a Smith number, since the sum of its digits (36) coincides with the sum of the digits of its prime factors.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a self number, because there is not a number n which added to its sum of digits gives 121749156.

It is not an unprimeable number, because it can be changed into a prime (121749157) by changing a digit.

It is a polite number, since it can be written in 14 ways as a sum of consecutive naturals, for example, 198306 + ... + 198918.

Almost surely, 2^121749156 is an apocalyptic number.

121749156 is the 11034-th square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 121749156

121749156 is an abundant number, since it is smaller than the sum of its proper divisors (197047245).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

121749156 is an frugal number, since it uses more digits than its factorization.

121749156 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1242 (or 618 counting only the distinct ones).

The product of its digits is 15120, while the sum is 36.

The cubic root of 121749156 is about 495.6274137818.

Multiplying 121749156 by its sum of digits (36), we get a square (4382969616 = 66204²).

121749156 divided by its sum of digits (36) gives a square (3381921 = 1839²).

The spelling of 121749156 in words is "one hundred twenty-one million, seven hundred forty-nine thousand, one hundred fifty-six".