661739416 has 32 divisors (see below), whose sum is σ = 1414808640. Its totient is φ = 287451648.

The previous prime is 661739401. The next prime is 661739431. The reversal of 661739416 is 614937166.

It is an interprime number because it is at equal distance from previous prime (661739401) and next prime (661739431).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 185376 + ... + 188911.

It is an arithmetic number, because the mean of its divisors is an integer number (44212770).

Almost surely, 2^661739416 is an apocalyptic number.

It is an amenable number.

661739416 is an abundant number, since it is smaller than the sum of its proper divisors (753069224).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

661739416 is a wasteful number, since it uses less digits than its factorization.

661739416 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 374323 (or 374319 counting only the distinct ones).

The product of its digits is 163296, while the sum is 43.

The square root of 661739416 is about 25724.2962197219. The cubic root of 661739416 is about 871.4229657412.

The spelling of 661739416 in words is "six hundred sixty-one million, seven hundred thirty-nine thousand, four hundred sixteen".