1201515541 has 8 divisors (see below), whose sum is σ = 1250895704. Its totient is φ = 1153025280.

The previous prime is 1201515533. The next prime is 1201515547. The reversal of 1201515541 is 1455151021.

It can be written as a sum of positive squares in 4 ways, for example, as 541539441 + 659976100 = 23271^2 + 25690^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1201515541 - 2³ = 1201515533 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1201515547) 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, 219720 + ... + 225121.

It is an arithmetic number, because the mean of its divisors is an integer number (156361963).

Almost surely, 2^1201515541 is an apocalyptic number.

It is an amenable number.

1201515541 is a deficient number, since it is larger than the sum of its proper divisors (49380163).

1201515541 is an equidigital number, since it uses as much as digits as its factorization.

1201515541 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 444951.

The product of its (nonzero) digits is 1000, while the sum is 25.

The square root of 1201515541 is about 34662.8841990969. The cubic root of 1201515541 is about 1063.1057428245.

Adding to 1201515541 its reverse (1455151021), we get a palindrome (2656666562).

It can be divided in two parts, 12015 and 15541, that added together give a square (27556 = 166²).

The spelling of 1201515541 in words is "one billion, two hundred one million, five hundred fifteen thousand, five hundred forty-one".