1561143701 has 16 divisors (see below), whose sum is σ = 1728633984. Its totient is φ = 1400514624.

The previous prime is 1561143691. The next prime is 1561143737. The reversal of 1561143701 is 1073411651.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 1561143701 - 2¹⁴ = 1561127317 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1561143761) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 694886 + ... + 697128.

It is an arithmetic number, because the mean of its divisors is an integer number (108039624).

Almost surely, 2^1561143701 is an apocalyptic number.

It is an amenable number.

1561143701 is a deficient number, since it is larger than the sum of its proper divisors (167490283).

1561143701 is a wasteful number, since it uses less digits than its factorization.

1561143701 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3740.

The product of its (nonzero) digits is 2520, while the sum is 29.

The square root of 1561143701 is about 39511.3110513939. The cubic root of 1561143701 is about 1160.0613574857.

The spelling of 1561143701 in words is "one billion, five hundred sixty-one million, one hundred forty-three thousand, seven hundred one".