1561220654 has 24 divisors (see below), whose sum is σ = 2735515728. Its totient is φ = 666308160.

The previous prime is 1561220603. The next prime is 1561220663. The reversal of 1561220654 is 4560221651.

It is a hoax number, since the sum of its digits (32) coincides with the sum of the digits of its distinct prime factors.

It is a self number, because there is not a number n which added to its sum of digits gives 1561220654.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 9434 + ... + 56669.

It is an arithmetic number, because the mean of its divisors is an integer number (113979822).

Almost surely, 2^1561220654 is an apocalyptic number.

1561220654 is a gapful number since it is divisible by the number (14) formed by its first and last digit.

1561220654 is a deficient number, since it is larger than the sum of its proper divisors (1174295074).

1561220654 is a wasteful number, since it uses less digits than its factorization.

1561220654 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 66360 (or 66353 counting only the distinct ones).

The product of its (nonzero) digits is 14400, while the sum is 32.

The square root of 1561220654 is about 39512.2848491453. The cubic root of 1561220654 is about 1160.0804180277.

The spelling of 1561220654 in words is "one billion, five hundred sixty-one million, two hundred twenty thousand, six hundred fifty-four".