1561677428 has 6 divisors (see below), whose sum is σ = 2732935506. Its totient is φ = 780838712.

The previous prime is 1561677427. The next prime is 1561677457. The reversal of 1561677428 is 8247761651.

It can be written as a sum of positive squares in only one way, i.e., 1163355664 + 398321764 = 34108^2 + 19958^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1561677427) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 195209675 + ... + 195209682.

It is an arithmetic number, because the mean of its divisors is an integer number (455489251).

Almost surely, 2^1561677428 is an apocalyptic number.

It is an amenable number.

1561677428 is a deficient number, since it is larger than the sum of its proper divisors (1171258078).

1561677428 is a wasteful number, since it uses less digits than its factorization.

1561677428 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 390419361 (or 390419359 counting only the distinct ones).

The product of its digits is 564480, while the sum is 47.

The square root of 1561677428 is about 39518.0645781141. The cubic root of 1561677428 is about 1160.1935438057.

The spelling of 1561677428 in words is "one billion, five hundred sixty-one million, six hundred seventy-seven thousand, four hundred twenty-eight".