61902932809 has 9 divisors (see below), whose sum is σ = 62984854087. Its totient is φ = 60839299984.

The previous prime is 61902932783. The next prime is 61902932837. The reversal of 61902932809 is 90823920916.

The square root of 61902932809 is 248803.

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., 55001975625 + 6900957184 = 234525^2 + 83072^2 .

It is not a de Polignac number, because 61902932809 - 2⁷ = 61902932681 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (61902932869) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 14677269 + ... + 14681485.

Almost surely, 2^61902932809 is an apocalyptic number.

61902932809 is the 248803-rd square number.

61902932809 is the 124402-nd centered octagonal number.

It is an amenable number.

61902932809 is a deficient number, since it is larger than the sum of its proper divisors (1081921278).

61902932809 is an frugal number, since it uses more digits than its factorization.

61902932809 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8552 (or 4276 counting only the distinct ones).

The product of its (nonzero) digits is 419904, while the sum is 49.

Multiplying 61902932809 by its sum of digits (49), we get a square (3033243707641 = 1741621²).

The spelling of 61902932809 in words is "sixty-one billion, nine hundred two million, nine hundred thirty-two thousand, eight hundred nine".